Re: Return Dataset to Business Layer & SHOW in datagrid in Presentation Layer [modified] - C# Discussion Boards

program is layering & ds in not known in form
first ds come in business layer then view in datagried
it is not easy my dear friend Confused | :confused:

I'm sorry I don't understand.

what do you mean by "ds in not known in form"?

An by this "first ds come in business layer then view in datagried"?
Do you have problem returnig the dataset from your bussines layer to your UI?

yes
first ds to business layer then view in UI layer & form

I got that from your anteriour posts.

But what is your problem? Passing data from the BLogic to the UI
or just the UI part?

[EDIT]

OK suppose that your UI is in the MyUI namespace.
The BussinessLayer is in the MyLogic namespace.

in order to populate your UI with data do something like this inside a click event for example:

private void btn1_Click(object sender, EventArgs null){
     dataGridView1.DataSource = MyLogic.MemberBL.GetDataSet().Tables[0];
     //where the GetDataSet() returns the ds from the BussinessLayer;
}

Just like d@nish said if on a different project/dll just add a reference to it.

my business layer is:

using System;<br />
using System.Collections.Generic;<br />
using System.Linq;<br />
using System.Text;<br />
<br />
namespace Library_Project<br />
{<br />
    class memberBL<br />
    {<br />
                    //Book properties<br />
            private String membercode;<br />
            private String name;<br />
            private String family;<br />
            private String shsh;<br />
            private String melicode;<br />
            private String tavalod;<br />
            private String shoghl;<br />
            private String tel;<br />
            private String mobile;<br />
            private String adr;<br />
            private String trkhozv;<br />
<br />
            private memberDA memberData;<br />
<br />
       // BUSINESS LOGIC Member <br />
       public memberBL()            <br />
       {<br />
         <br />
           //Data access layer!<br />
     <br />
           memberData = new memberDA();<br />
<br />
       }<br />
       /// <SUMMARY><br />
       /// Property BookCode (String)<br />
       /// </SUMMARY><br />
       public String DatasetData<br />
       {<br />
           get<br />
           {<br />
               return this.DatasetData;<br />
           }<br />
           set<br />
           {<br />
               this.DatasetData = value;<br />
<br />
<br />
           }<br />
       }<br />
       /// <SUMMARY><br />
       /// Property BookCode (String)<br />
       /// </SUMMARY><br />
       public String Membercode<br />
       {<br />
           get<br />
           {<br />
               return this.membercode;<br />
           }<br />
           set<br />
           {<br />
               this.membercode = value;<br />
<br />
<br />
           }<br />
       }<br />
 <br />
            /// <SUMMARY><br />
            /// Property BooktName (String)<br />
            /// </SUMMARY><br />
            public String Name <br />
            {<br />
      <br />
                  get<br />
                  {<br />
                      return this.name;<br />
                  }<br />
                  set<br />
                  {<br />
                        try<br />
                        {<br />
                            this.name = value;<br />
<br />
                            if (this.name == "")<br />
                              {<br />
                                    throw new Exception(<br />
                                      "لطفا نام عضو را وارد نمایید");<br />
                              }<br />
                        }<br />
                        catch(Exception e)<br />
                        {<br />
                              throw new Exception(e.Message.ToString());<br />
                        }<br />
                  }<br />
            }<br />
 <br />
            /// <SUMMARY><br />
            /// Property ISBN (String)<br />
            /// </SUMMARY><br />
            public String Familly<br />
            {<br />
                  get<br />
                  {<br />
                        return this.family;<br />
                  }<br />
                  set<br />
                  {<br />
                        //could be more checkings here eg revmove ' chars<br />
                        //change to proper case<br />
                        //blah blah<br />
                        this.family = value;<br />
                        if (this.family == "")<br />
                        {<br />
                              throw new Exception("لطفا نام خانوادگی عضو رو وارد نمایید");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
<br />
            /// <SUMMARY><br />
            /// Property Nasher (String)<br />
            /// </SUMMARY><br />
            public String Shsh<br />
            {<br />
                  get<br />
                  {<br />
                      return this.shsh;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.shsh = value;<br />
<br />
                      if (this.shsh == "")<br />
                        {<br />
                              throw new Exception("لطفا شماره شناسنامه را وارد نمایید");<br />
                        }<br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property ISBN (String)<br />
            /// </SUMMARY><br />
            public String Melicode<br />
            {<br />
                  get<br />
                  {<br />
                        return this.melicode;<br />
                  }<br />
                  set<br />
                  {<br />
                        //could be more checkings here eg revmove ' chars<br />
                        //change to proper case<br />
                        //blah blah<br />
                        this.melicode = value;<br />
                        if (this.melicode == "")<br />
                        {<br />
                              throw new Exception("لطفا کد ملی عضو رو وارد نمایید");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property Nasher (String)<br />
            /// </SUMMARY><br />
            public String Tavalod<br />
            {<br />
                  get<br />
                  {<br />
                      return this.tavalod;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.tavalod = value;<br />
<br />
                      if (this.tavalod == "")<br />
                        {<br />
                              throw new Exception("لطفا تاریخ تولد رو وارد نمایید");<br />
                        }<br />
                  }<br />
            }<br />
<br />
 <br />
            /// <SUMMARY><br />
            /// Property Mozoe Ketab (String)<br />
            /// </SUMMARY><br />
            public String Shoghl<br />
            {<br />
                  get<br />
                  {<br />
                      return this.shoghl;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.shoghl = value;<br />
                      if (this.shoghl == "")<br />
                        {<br />
                              throw new Exception("لطفا شغل رو انتخاب کنید");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property Mozoe Ketab (String)<br />
            /// </SUMMARY><br />
            public String Tel<br />
            {<br />
                  get<br />
                  {<br />
                      return this.tel;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.tel = value;<br />
                      if (this.tel == "")<br />
                        {<br />
                            throw new Exception("لطفا شماره  تلفن را وارد نمایید ");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property Mozoe Ketab (String)<br />
            /// </SUMMARY><br />
            public String Mobile<br />
            {<br />
                  get<br />
                  {<br />
                      return this.mobile;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.mobile = value;<br />
                      if (this.mobile == "")<br />
                        {<br />
                            throw new Exception("لطفا شماره موبایل را وارد نمایید ");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property Mozoe Ketab (String)<br />
            /// </SUMMARY><br />
            public String Adr<br />
            {<br />
                  get<br />
                  {<br />
                      return this.adr;<br />
                  }<br />
                  set<br />
                  {<br />
                      this.adr = value;<br />
                      if (this.adr == "")<br />
                        {<br />
                            throw new Exception("لطفا آدرس را وارد نمایید");<br />
                        }<br />
 <br />
                  }<br />
            }<br />
            /// <SUMMARY><br />
            /// Property Mozoe Ketab (String)<br />
            /// </SUMMARY><br />
            public String Trkhozv<br />
            {<br />
                get<br />
                {<br />
                    return this.trkhozv;<br />
                }<br />
                set<br />
                {<br />
                    this.trkhozv = value;<br />
<br />
<br />
                }<br />
            }<br />
            /// <SUMMARY><br />
            /// Function Add new customer. Calls <br />
            /// the function in Data layer.<br />
            /// </SUMMARY><br />
            public void Add()<br />
            {<br />
                  memberData.Add(this);<br />
            }<br />
 <br />
 <br />
            /// <SUMMARY><br />
            /// Function Update customer details. <br />
            /// Calls the function in Data layer.<br />
            /// </SUMMARY><br />
            public void Update()<br />
            {<br />
                memberData.Update(this);<br />
            }<br />
<br />
            /// <SUMMARY><br />
            /// Function View Member details. <br />
            /// Calls the function in Data layer.<br />
            /// </SUMMARY><br />
         <br />
    }<br />
}

My data Layer IS :

using System;
using System.Data.OleDb;
using System.Data;
using System.Text;

namespace Library_Project
{
    class memberDA
    {
        private OleDbConnection cnn;
        //change connection string as per the 
        //folder you unzip the files
        private const string CnnStr = 
          "Provider=Microsoft.Jet.OLEDB.4.0;Data " +
          "Source= D:\\Data\\Library.mdb;"; 
            
        //local variables
        private String strTable="";
        private String strFields="";
        private String strValues="";
        private String insertStr="";
        
        //this needs to be changed based on Books 
        //table fields' Name of the database!
        private const String thisTable = "tblmembers";
        private const String member_code = "membercode";
        private const String member_name = "name";
        private const String member_family = "family";
        private const String member_shsh = "shsh";
        private const String member_melicode = "melicode";
        private const String member_tavalod = "tavalod";
        private const String member_shoghl = "shoghl";
        private const String member_tel = "tel";
        private const String member_mobile = "mobile";
        private const String member_adr = "adr";
        private const String member_trkhozv = "trkhozv";
        private memberBL memberLogic;

        public memberDA()
        {
           
        }

        public memberDA(memberBL member)
       
        {
            // A reference of the business object class
            memberLogic = new memberBL();
        }
        
        //standard dataset function that adds a new customer

        public void Add(memberBL member)
        {

            String str = BuildAddString(member);
            
            OpenCnn();

            //Open command option - cnn parameter is imporant
            OleDbCommand cmd = new OleDbCommand(str,cnn);


            //execute connection
            cmd.ExecuteNonQuery();
            
            // close connection
            CloseCnn();
            
        }
        
        //standard dataset function that updates 
        //details of a customer based on ID
        public void Update(memberBL member)
        {
            OpenCnn();
            
            String selectStr = "UPDATE " + thisTable +
                " set " + member_name + " = '" + member.Name + "'" +
                ", " + member_family + " = '" + member.Familly + "'" +
                ", " + member_shsh + " = '" + member.Shsh + "'" +
                ", " + member_melicode + " = '" + member.Melicode + "'" +
                ", " + member_tavalod + " = '" + member.Tavalod + "'" +
                ", " + member_shoghl + " = '" + member.Shoghl + "'" +
                ", " + member_tel + " = '" + member.Tel + "'" +
                ", " + member_mobile + " = '" + member.Mobile + "'" +
                ", " + member_adr + " = '" + member.Adr + "'" +
                " where member_code = '" + member.Membercode  + "'";

            OleDbCommand cmd = new OleDbCommand(selectStr,cnn);

            cmd.ExecuteNonQuery();
            
            CloseCnn();
        }
        
        //standard dataset function that finds and 
        //return the detail of a customer in a dataset
        public DataSet Find(String argStr)
        {
            DataSet ds=null;

            try
            {
                OpenCnn();
            
                String selectStr = "select * from " + thisTable + 
                              " where member_code = '" + argStr + "'";
                OleDbDataAdapter da = 
                       new OleDbDataAdapter(selectStr,cnn);
                ds = new DataSet();
                da.Fill(ds,thisTable);
            
                CloseCnn();

                
            }
            catch(Exception e)
            {
                String Str = e.Message;
            }

            return ds;
        }

        //standard dataset function that finds and 
        //return the detail of a customer in a dataset
        public DataSet View()
        {
            DataSet ds = null;

            try
            {
                OpenCnn();
                
                String selectStr = "select * from " + thisTable + "'";
                
                OleDbDataAdapter da =new OleDbDataAdapter(selectStr, cnn);
                
                ds = new DataSet();
                
                da.Fill(ds, thisTable);
                
                CloseCnn();
            }
            catch (Exception e)
            {
                String Str = e.Message;
            }

            return ds;
        }

        private void OpenCnn()
        {
            // initialise connection
            String cnnStr = CnnStr;
            cnn = new OleDbConnection(cnnStr);
            // open connection
            cnn.Open();
        }

        private void CloseCnn()
        {
            // 5- step five
            cnn.Close();
        }
        
        // just a supporting function that builds 
        // and return the insert string for dataset.
        private String BuildAddString(memberBL member)
        {
            // these are the constants as 
            // set in the top of this module.
            strTable="Insert into " + thisTable;
            strFields = " (" + member_code +
            "," + member_name +
            "," + member_family +
            "," + member_shsh +
            "," + member_melicode +
            "," + member_tavalod +
            "," + member_shoghl +
            "," + member_tel +
            "," + member_mobile +
            "," + member_adr +
            "," + member_trkhozv + ")";
            
            //these are the attributes of the 
            //customer business object.
            strValues = " Values ( '" + member.Membercode +
            "' , '" + member.Name +
            "' , '" + member.Familly +
            "' , '" + member.Shsh +
            "' , '" + member.Melicode +
            "' , '" + member.Tavalod +
            "' , '" + member.Shoghl +
            "' , '" + member.Tel +
            "' , '" + member.Mobile +
            "' , '" + member.Adr +
            "' , '" + member.Trkhozv + "' )";

            insertStr = strTable + strFields + strValues;
            
            return insertStr;
            
        }

    }
}

HOW Return ds to Form?

Somthing like this:

//in the business layer create a method or property that gets the
//data from the DataLayer. Something like this:
public DataSet GetDatas(){
     return memberData.View();
}

//Now in the UI do something like this
LibraryProject.MemberBL bl = new LibraryProject.MemberBL();

dataGridView1.DataSource = bl.GetDatas().Tables[0];

[Edit]Fixed pre tags[/EDIT]

modified on Sunday, February 21, 2010 10:58 PM

If everything is in same project, create an instance of your BL class and then call the method which returns the dataset.

If BL is in separate project, add a reference to that project in your UI project and then do the same.

My Business Lyaer Is:

using System;
using System.Collections.Generic;
using System.Data.OleDb;
using System.Text;
using System.Data;

namespace Library_Project
{
    class memberBL
    {
                    //Book properties
            private String membercode;
            private String name;
            private String family;
            private String shsh;
            private String melicode;
            private String tavalod;
            private String shoghl;
            private String tel;
            private String mobile;
            private String adr;
            private String trkhozv;

            private memberDA memberData;

       // BUSINESS LOGIC Member 
       public memberBL()            
       {
         
           //Data access layer!
     
           memberData = new memberDA();

       }
       /// <SUMMARY>
       /// Property BookCode (String)
       /// </SUMMARY>
       public String Membercode
       {
           get
           {
               return this.membercode;
           }
           set
           {
               this.membercode = value;


           }
       }
 
            /// <SUMMARY>
            /// Property BooktName (String)
            /// </SUMMARY>
            public String Name 
            {
      
                  get
                  {
                      return this.name;
                  }
                  set
                  {
                        try
                        {
                            this.name = value;

                            if (this.name == "")
                              {
                                    throw new Exception(
                                      "لطفا نام عضو را وارد نمایید");
                              }
                        }
                        catch(Exception e)
                        {
                              throw new Exception(e.Message.ToString());
                        }
                  }
            }
 
            /// <SUMMARY>
            /// Property ISBN (String)
            /// </SUMMARY>
            public String Familly
            {
                  get
                  {
                        return this.family;
                  }
                  set
                  {
                        //could be more checkings here eg revmove ' chars
                        //change to proper case
                        //blah blah
                        this.family = value;
                        if (this.family == "")
                        {
                              throw new Exception("لطفا نام خانوادگی عضو رو وارد نمایید");
                        }
 
                  }
            }

            /// <SUMMARY>
            /// Property Nasher (String)
            /// </SUMMARY>
            public String Shsh
            {
                  get
                  {
                      return this.shsh;
                  }
                  set
                  {
                      this.shsh = value;

                      if (this.shsh == "")
                        {
                              throw new Exception("لطفا شماره شناسنامه را وارد نمایید");
                        }
                  }
            }
            /// <SUMMARY>
            /// Property ISBN (String)
            /// </SUMMARY>
            public String Melicode
            {
                  get
                  {
                        return this.melicode;
                  }
                  set
                  {
                        //could be more checkings here eg revmove ' chars
                        //change to proper case
                        //blah blah
                        this.melicode = value;
                        if (this.melicode == "")
                        {
                              throw new Exception("لطفا کد ملی عضو رو وارد نمایید");
                        }
 
                  }
            }
            /// <SUMMARY>
            /// Property Nasher (String)
            /// </SUMMARY>
            public String Tavalod
            {
                  get
                  {
                      return this.tavalod;
                  }
                  set
                  {
                      this.tavalod = value;

                      if (this.tavalod == "")
                        {
                              throw new Exception("لطفا تاریخ تولد رو وارد نمایید");
                        }
                  }
            }

 
            /// <SUMMARY>
            /// Property Mozoe Ketab (String)
            /// </SUMMARY>
            public String Shoghl
            {
                  get
                  {
                      return this.shoghl;
                  }
                  set
                  {
                      this.shoghl = value;
                      if (this.shoghl == "")
                        {
                              throw new Exception("لطفا شغل رو انتخاب کنید");
                        }
 
                  }
            }
            /// <SUMMARY>
            /// Property Mozoe Ketab (String)
            /// </SUMMARY>
            public String Tel
            {
                  get
                  {
                      return this.tel;
                  }
                  set
                  {
                      this.tel = value;
                      if (this.tel == "")
                        {
                            throw new Exception("لطفا شماره  تلفن را وارد نمایید ");
                        }
 
                  }
            }
            /// <SUMMARY>
            /// Property Mozoe Ketab (String)
            /// </SUMMARY>
            public String Mobile
            {
                  get
                  {
                      return this.mobile;
                  }
                  set
                  {
                      this.mobile = value;
                      if (this.mobile == "")
                        {
                            throw new Exception("لطفا شماره موبایل را وارد نمایید ");
                        }
 
                  }
            }
            /// <SUMMARY>
            /// Property Mozoe Ketab (String)
            /// </SUMMARY>
            public String Adr
            {
                  get
                  {
                      return this.adr;
                  }
                  set
                  {
                      this.adr = value;
                      if (this.adr == "")
                        {
                            throw new Exception("لطفا آدرس را وارد نمایید");
                        }
 
                  }
            }
            /// <SUMMARY>
            /// Property Mozoe Ketab (String)
            /// </SUMMARY>
            public String Trkhozv
            {
                get
                {
                    return this.trkhozv;
                }
                set
                {
                    this.trkhozv = value;


                }
            }
            /// <SUMMARY>
            /// Function Add new customer. Calls 
            /// the function in Data layer.
            /// </SUMMARY>
            public void Add()
            {
                  memberData.Add(this);
            }
 
 
            /// <SUMMARY>
            /// Function Update customer details. 
            /// Calls the function in Data layer.
            /// </SUMMARY>
            public void Update()
            {
                memberData.Update(this);
            }

            /// <SUMMARY>
            /// Function View Member details. 
            /// Calls the function in Data layer.
            /// </SUMMARY>
            ///  
         
    }
}

& My Data Layer Is:

using System;
using System.Data.OleDb;
using System.Data;
using System.Text;

namespace Library_Project
{
    class memberDA
    {
        private OleDbConnection cnn;
        //change connection string as per the 
        //folder you unzip the files
        private const string CnnStr = 
          "Provider=Microsoft.Jet.OLEDB.4.0;Data " +
          "Source= D:\\Data\\Library.mdb;"; 
            
        //local variables
        private String strTable="";
        private String strFields="";
        private String strValues="";
        private String insertStr="";
        
        //this needs to be changed based on Books 
        //table fields' Name of the database!
        private const String thisTable = "tblmembers";
        private const String member_code = "membercode";
        private const String member_name = "name";
        private const String member_family = "family";
        private const String member_shsh = "shsh";
        private const String member_melicode = "melicode";
        private const String member_tavalod = "tavalod";
        private const String member_shoghl = "shoghl";
        private const String member_tel = "tel";
        private const String member_mobile = "mobile";
        private const String member_adr = "adr";
        private const String member_trkhozv = "trkhozv";
        private memberBL memberLogic;

        public memberDA()
        {
           
        }

        public memberDA(memberBL member)
       
        {
            // A reference of the business object class
            memberLogic = new memberBL();
        }
        
        //standard dataset function that adds a new customer

        public void Add(memberBL member)
        {

            String str = BuildAddString(member);
            
            OpenCnn();

            //Open command option - cnn parameter is imporant
            OleDbCommand cmd = new OleDbCommand(str,cnn);


            //execute connection
            cmd.ExecuteNonQuery();
            
            // close connection
            CloseCnn();
            
        }
        
        //standard dataset function that updates 
        //details of a customer based on ID
        public void Update(memberBL member)
        {
            OpenCnn();
            
            String selectStr = "UPDATE " + thisTable +
                " set " + member_name + " = '" + member.Name + "'" +
                ", " + member_family + " = '" + member.Familly + "'" +
                ", " + member_shsh + " = '" + member.Shsh + "'" +
                ", " + member_melicode + " = '" + member.Melicode + "'" +
                ", " + member_tavalod + " = '" + member.Tavalod + "'" +
                ", " + member_shoghl + " = '" + member.Shoghl + "'" +
                ", " + member_tel + " = '" + member.Tel + "'" +
                ", " + member_mobile + " = '" + member.Mobile + "'" +
                ", " + member_adr + " = '" + member.Adr + "'" +
                " where member_code = '" + member.Membercode  + "'";

            OleDbCommand cmd = new OleDbCommand(selectStr,cnn);

            cmd.ExecuteNonQuery();
            
            CloseCnn();
        }
        
        //standard dataset function that finds and 
        //return the detail of a customer in a dataset
        public DataSet Find(String argStr)
        {
            DataSet ds=null;

            try
            {
                OpenCnn();
            
                String selectStr = "select * from " + thisTable + 
                              " where member_code = '" + argStr + "'";
                OleDbDataAdapter da = 
                       new OleDbDataAdapter(selectStr,cnn);
                ds = new DataSet();
                da.Fill(ds,thisTable);
            
                CloseCnn();

                
            }
            catch(Exception e)
            {
                String Str = e.Message;
            }

            return ds;
        }

        //standard dataset function that finds and 
        //return the detail of a customer in a dataset
        public DataSet View()
        {
            DataSet ds = null;

            try
            {
                OpenCnn();
                
                String selectStr = "select * from " + thisTable + "'";
                
                OleDbDataAdapter da =new OleDbDataAdapter(selectStr, cnn);
                
                ds = new DataSet();
                
                da.Fill(ds, thisTable);
                
                CloseCnn();
            }
            catch (Exception e)
            {
                String Str = e.Message;
            }

            return ds;
        }

        private void OpenCnn()
        {
            // initialise connection
            String cnnStr = CnnStr;
            cnn = new OleDbConnection(cnnStr);
            // open connection
            cnn.Open();
        }

        private void CloseCnn()
        {
            // 5- step five
            cnn.Close();
        }
        
        // just a supporting function that builds 
        // and return the insert string for dataset.
        private String BuildAddString(memberBL member)
        {
            // these are the constants as 
            // set in the top of this module.
            strTable="Insert into " + thisTable;
            strFields = " (" + member_code +
            "," + member_name +
            "," + member_family +
            "," + member_shsh +
            "," + member_melicode +
            "," + member_tavalod +
            "," + member_shoghl +
            "," + member_tel +
            "," + member_mobile +
            "," + member_adr +
            "," + member_trkhozv + ")";
            
            //these are the attributes of the 
            //customer business object.
            strValues = " Values ( '" + member.Membercode +
            "' , '" + member.Name +
            "' , '" + member.Familly +
            "' , '" + member.Shsh +
            "' , '" + member.Melicode +
            "' , '" + member.Tavalod +
            "' , '" + member.Shoghl +
            "' , '" + member.Tel +
            "' , '" + member.Mobile +
            "' , '" + member.Adr +
            "' , '" + member.Trkhozv + "' )";

            insertStr = strTable + strFields + strValues;
            
            return insertStr;
            
        }

    }
}

How ds trasnsfer to Business Layer & Then View in form

modified on Sunday, February 21, 2010 9:44 AM

How ds trasnsfer to Business Layer & Then View in form?
BUSINESS LAYER & DATA LAYER CODE IS above

I am trying to convert some code to .net framework 2.0 from .net framework 3.0.

the code of .net framework 3.5 is:

if (mItems.Exists(b => string.Compare(b.FileName, item.FileName, StringComparison.OrdinalIgnoreCase) == 0))
                        return;

It can run in .net framework 3.5 and can not run in .net framework 2.0.

Could someone tell me where the defferent things between 3.5 from 2.0 in the code are.

Lambda expressions were introduced in .Net 3.0. This should be enough:

if (mItems.Exists(string.Compare(b.FileName, item.FileName, StringComparison.OrdinalIgnoreCase) == 0))
                        return;

Thanks!
There is another problem. The parameter "b" whose type as same as parameter "item" is not defined.
And the parameter "b" have not defined anywhere. I try to change the name of parameter "b" to "a",it also could run. I am puzzled about this.

"The left side of the lambda operator specifies the input parameters (if any) and the right side holds the expression or statement block. "

So b (and a) are your input parameters.

Me, I'm dishonest. And a dishonest man you can always trust to be dishonest.
Honestly. It's the honest ones you want to watch out for...

Thanks!
I have googled the lambda operator specifies and research it.There are some differences in syntax.
In .net 2.0, it need use delegate to define a virtual method instead of the lambda expressions.

Thank you.

That expression means that A variable "b" would be sent and the expression on the right side of "=>" would be executed on it. Now, you can see through your code and modify it accordingly. You can have a separate method that takes a variable of same type as "b" and returns the result or can declare the variable in the current method/class and use it.

If you are using VS2008, you can set the target framework as 2.0 and the original code should work.

Thanks!
I just back from a business trip. I have googled the lambda operator specifies and research it.There are some differences in syntax.
In .net 2.0, it need use delegate to define a virtual method instead of the lambda expressions.

Thank you.

But you can use C# 3 with .NET 2.0

Yes, I can.
I just want to konw why I could not debug the code successed in .net 2.0.

In that line of code, there shouldn't be any differences.

Lambda expressions compile to the same IL as anonymous methods in C# 2.0; it shouldn't be the problem.
The "Exists" method already was present for List<T> in .NET 2.0, so I don't see why your code would not run on .NET 2.0.

Generally, if you use the C# 3.0 compiler without setting any references on .NET 3.x assemblies (e.g. System.Core), the resulting binary will run on .NET 2.0.

What does "it can not run" mean? Do you get an exception? What is the error message?

Thanks!
I just back from a business trip. I have googled the lambda operator specifies and research it.There are some differences in syntax.
In .net 2.0, it need use delegate to define a virtual method instead of the lambda expressions.

"it can not run", I said, means that, I could not debug the code in .net 2.0. And I just want to konw why it was happened.

Thank you.

Why can't we just right click, insert > picture??
Why doesn't it work?? I simply get nothing when I do that!!

If you're familiar with this problem, can you shed some light on how to set it at runtime from a path in the hard disk rather than from a database field.. Probably as a parameter or whatever way it works.

Thanks!

Hi ,
Is there any good tools to create a good framework(Busines Logic and Datalayer) from a database ?

With Warm Regards...

you can try NHibernate[^] or Microsoft ADO.Net Entity Framework[^]

MyGeneration[^] can be used to generate sourcecode that's based on a database-structure Smile | :)

I are Troll Suspicious | :suss:

I have a datagrid that is being populated correctly. yet only the first row shows in the grid. I have a second row that shows nothing. However, if i click on the second row then I see the data. Is there some kinda setting I'm missing in properties or is it something else?