How to invoke class method in asp.net

Question

0.00/5 (No votes)

See more:

I am created one class file in asp.net i want to use the class method on other pages.

C#

using Microsoft.VisualBasic;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Diagnostics;
using System.Data.Common;
public class General_function
{
    internal System.Windows.Forms.DataGridView DG_ItemShow;
    public static object Get_Single_Value(string SQLQuery)
    {
        try
        {
            object SingleValue = null;
            DbConnection cn = database_Object.GetConnection(database_Object.Provider);
            DbCommand cmd = database_Object.GetCommand(database_Object.Provider);
            if (cn.State == ConnectionState.Closed)
            {
                cn.ConnectionString = My.Settings.Trasns_DataConnectionString;
                cn.Open();
            }
            cmd.Connection = cn;
            cmd.CommandText = SQLQuery;

            SingleValue = cmd.ExecuteScalar;

            return SingleValue;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("error in Get_Single_Value :  " + ex.Message);
        }
    }

    public static long get_Max_value(string tablename, string fieldname)
    {
        try
        {
            long maxvalue = 0;
            DbConnection cn = database_Object.GetConnection(database_Object.Provider);
            DbCommand cmd = database_Object.GetCommand(database_Object.Provider);
            if (cn.State == ConnectionState.Closed)
            {
                cn.ConnectionString = My.Settings.Trasns_DataConnectionString;
                cn.Open();
            }
            cmd.Connection = cn;
            cmd.CommandText = "select max(" + fieldname + ") From " + tablename;
            string res = null;
            res = cmd.ExecuteScalar.ToString;
            if (string.IsNullOrEmpty(res))
            {
                maxvalue = 0;
            }
            else
            {
                maxvalue = long.Parse(res);
            }
            return maxvalue;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("Error in get_Max_value" + ex.Message);
        }
    }
    public static int Save_Record(ArrayList Al, string TableName)
    {
        try
        {
            int Retval = 0;
            Trasns_DataDataSet ds = new Trasns_DataDataSet();
            DataTable dt = ds.Tables(TableName);
            ArrayList tal = new ArrayList();
            foreach (DataColumn cl in dt.Columns)
            {
                tal.Add(cl.ColumnName);
            }

            DbConnection cnn = default(DbConnection);
            cnn = database_Object.GetConnection(database_Object.Provider);
            cnn.ConnectionString = My.Settings.Trasns_DataConnectionString;
            cnn.Open();
            DbCommand cmd1 = default(DbCommand);
            cmd1 = database_Object.GetCommand(database_Object.Provider);
            cmd1.Connection = cnn;
            string n = null;
            for (int i = 0; i <= tal.Count - 1; i++)
            {
                n = "@" + tal(i).ToString;
                DbParameter pa = database_Object.GetParameter(database_Object.Provider);
                pa.ParameterName = n;
                pa.Value = Al(i);
                cmd1.Parameters.Add(pa);
            }

            n = "";
            string v = "";
            string sqlstr = "insert into " + TableName + " (";
            for (int i = 0; i <= tal.Count - 1; i++)
            {
                n = n + "," + tal(i).ToString;
                v = v + ",@" + tal(i).ToString;
            }
            n = Strings.Right(n, Strings.Len(n) - 1);
            v = Strings.Right(v, Strings.Len(v) - 1);
            sqlstr = sqlstr + n + ") values (" + v + ")";
            cmd1.CommandText = sqlstr;
            Retval = cmd1.ExecuteNonQuery;
            return Retval;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("error in  Save_Record :  " + ex.Message);
        }
    }

    public static int Delete_Record(ArrayList AlName, ArrayList AlValue, string TableName)
    {
        try
        {
            int Retval = 0;
            DbConnection cnn = default(DbConnection);
            cnn = database_Object.GetConnection(database_Object.Provider);
            cnn.ConnectionString = My.Settings.Trasns_DataConnectionString;
            cnn.Open();
            DbCommand cmd1 = default(DbCommand);
            cmd1 = database_Object.GetCommand(database_Object.Provider);
            cmd1.Connection = cnn;
            string m = null;
            for (int i = 0; i <= AlName.Count - 1; i++)
            {
                m = "@" + AlName(i).ToString;
                DbParameter pa = database_Object.GetParameter(database_Object.Provider);
                pa.ParameterName = m;
                pa.Value = AlValue(i);
                cmd1.Parameters.Add(pa);
            }

            string sqlstr = "delete from " + TableName + " where ";

            string v = "";
            for (int i = 0; i <= AlName.Count - 1; i++)
            {
                v = v + " And " + AlName(i).ToString + "=@" + AlName(i).ToString;
            }
            v = Strings.Right(v, Strings.Len(v) - 4);
            sqlstr = sqlstr + v;
            cmd1.CommandText = sqlstr;
            Retval = cmd1.ExecuteNonQuery;
            return Retval;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("error in Delete_Record :  " + ex.Message);
        }
    }
    public static int Modify_Record(ArrayList AlName, ArrayList AlValue, ArrayList AlPKName, ArrayList AlPKValue, string TableName)
    {
        try
        {
            int Retval = 0;
            DbConnection cnn = default(DbConnection);
            cnn = database_Object.GetConnection(database_Object.Provider);
            cnn.ConnectionString = My.Settings.Trasns_DataConnectionString;
            cnn.Open();
            DbCommand cmd1 = default(DbCommand);
            cmd1 = database_Object.GetCommand(database_Object.Provider);
            cmd1.Connection = cnn;
            string m = null;
            //values parameters
            for (int i = 0; i <= AlName.Count - 1; i++)
            {
                m = "@" + AlName(i).ToString;
                DbParameter pa = database_Object.GetParameter(database_Object.Provider);
                pa.ParameterName = m;
                pa.Value = AlValue(i);
                cmd1.Parameters.Add(pa);
            }

            //primary key column parameters
            for (int i = 0; i <= AlPKName.Count - 1; i++)
            {
                m = "@" + AlPKName(i).ToString;
                DbParameter pa = database_Object.GetParameter(database_Object.Provider);
                pa.ParameterName = m;
                pa.Value = AlPKValue(i);
                cmd1.Parameters.Add(pa);
            }
            string sqlstr = "update " + TableName + " set ";

            string v = "";
            for (int i = 0; i <= AlName.Count - 1; i++)
            {
                v = v + "," + AlName(i).ToString + "=@" + AlName(i).ToString;
            }
            string w = "";
            for (int i = 0; i <= AlPKName.Count - 1; i++)
            {
                w = w + " And " + AlPKName(i).ToString + "=@" + AlPKName(i).ToString;
            }
            v = Strings.Right(v, Strings.Len(v) - 1);
            w = Strings.Right(w, Strings.Len(w) - 4);
            sqlstr = sqlstr + v + " Where " + w;
            cmd1.CommandText = sqlstr;
            Retval = cmd1.ExecuteNonQuery;
            return Retval;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("error in Modify_Record :  " + ex.Message);
        }
    }

    


    public static DataTable RecordSearch(string SqlString, string TableName)
    {
        try
        {
            DbConnection cnn = default(DbConnection);
            cnn = database_Object.GetConnection(database_Object.Provider);
            cnn.ConnectionString = My.Settings.Trasns_DataConnectionString;
            cnn.Open();
            Trasns_DataDataSet ds = new Trasns_DataDataSet();
            DataTable dt = default(DataTable);
            DbDataAdapter da = database_Object.GetAdapter(database_Object.Provider);
            DbCommand cmd = database_Object.GetCommand(database_Object.Provider);
            cmd.Connection = cnn;
            cmd.CommandText = SqlString;
            da.SelectCommand = cmd;
            da.Fill(ds, TableName);
            dt = ds.Tables(TableName);

            cnn.Close();
            cmd.Dispose();
            da.Dispose();
            cnn.Dispose();
            return dt;
        }
        catch (Exception ex)
        {
            Interaction.MsgBox("error in RecordSearch :  " + ex.Message);
        }
    }
   


    }
   
}

How can call the Get_Single_value()method in the other pages.
How can call the Delete_Record ()method in the other pages.
Please help me..
Thanks in advance...

Posted 20-Nov-13 23:03pm

basurajkumbhar

Updated 20-Nov-13 23:29pm

v3

Add a Solution

Comments

I.explore.code 21-Nov-13 5:07am

are u saying you don't know how to use classes and objects? Or instantiate/create references to classes? If yes, then i would recommend reading up on OOP a little...

Rockstar_ 21-Nov-13 5:07am

Please add namespace for the above class and import the namespace to the page where you want to access, then classname.methodname() you call.

basurajkumbhar 21-Nov-13 5:13am

it give error like
Error The type or namespace name 'General_function' could not be found

Rockstar_ 21-Nov-13 5:21am

namespace somename
{
public class General_function
{
public static object Get_Single_Value(string SQLQuery)
{
try
{
object SingleValue = null;
DbConnection cn = database_Object.GetConnection(database_Object.Provider);
DbCommand cmd = database_Object.GetCommand(database_Object.Provider);
if (cn.State == ConnectionState.Closed)
{
cn.ConnectionString = My.Settings.Trasns_DataConnectionString;
cn.Open();
}
cmd.Connection = cn;
cmd.CommandText = SQLQuery;

SingleValue = cmd.ExecuteScalar;

return SingleValue;
}
}

}

Now import somename in the page where you want,
ex: using somename;
then access the method with class name.

General_function.Get_Single_Value(you Query);

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Nicholas Marty · Answer 1 · 2013-11-20T23:13:00

as this is a staic method:

Just add this line wherever you'd like to use it.

C#

General_function.Get_Single_Value("Your SQL Query goes here");

However this method might not be threadsafe as multiple threads could access the database_Object at once (which has to bee a static object too). You'll need to make sure that your database_Objects are threadsafe.

In addition you should make sure to release the resources after the call otherwise you might end up with lots of open connection (running into problems if you're using a connection pooling mechanism)

If the DbConnection and DbCommand implement the IDisposable Interface use them like this:

C#

using(var cn = database_Object.GetConnection(database_Object.Provider)) {
   if(cn.State == ConnectionState.Closed) {
      cn.ConnectionString = My.Settings.Trasns_DataConnectionString;
      cn.Open();
   }
   using(var cmd = database_Object.GetCommand(database_Object.Provider)){
      cmd.Connection = cn;
      cmd.CommandText = SQLQuery; 
      return cmd.ExecuteScalar; 
   }
}

You won't even have to use exception handling to close the connections as the using statement takes care of disposing those objects.