C# Discussion Boards - CodeProject

Re: What's The Best Way To Do This?

Rob Philpott1-Nov-17 3:04

Rob Philpott

1-Nov-17 3:04

One of the best answers I've read!

Regards,
Rob Philpott.

Re: What's The Best Way To Do This?

peterkmx2-Nov-17 3:49

peterkmx

2-Nov-17 3:49

wow ... this is also my preferred approach for settings: serializing / deserializing a composed object to XML, like a tree. Each component can have indeed its GUI view - a property grid or conventional GUI elements ... (btw, I upvoted your answer ...)

Re: What's The Best Way To Do This?

Gerry Schmitz2-Nov-17 5:31

Gerry Schmitz

2-Nov-17 5:31

Thank you!

And each "property" of the "parm class" can have "intelligence"; versus what amounts to "name / value" pairs.

I've swung to adding many "getters" to my classes to simplify running "Fahrenheit versus Centigrade"; 3rd party test versus production credentials; "automatic" units conversion; "Developer / back door" mode; etc.

The "getters" know what context they are running under and return the appropriate values.

One's code starts to look like pseudo-english and becomes very robust (.IsXxxx; .HasXxxx; etc).

"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal

Re: What's The Best Way To Do This?

Pete O'Hanlon31-Oct-17 21:45

Pete O'Hanlon

31-Oct-17 21:45

Just off the top of my head:

public abstract class SettingBase
{
  public string Key { get; set; }
  public string Description { get; set; }
}
public abstract SettingBase<T> : SettingBase
{
  public T SettingValue { get; set; }
  public T MinValue { get; set; }
  public T MaxValue { get; set; }
}

public class SettingDouble : SettingBase<double>
{
}
public class SettingInt : SettingBase<int>
{
}
...
public List<SettingBase> MySettings { get; set; }

This doesn't remove the need for your base classes, but it does remove some of the duplication you have in your codebase.

This space for rent

Re: What's The Best Way To Do This?

Kevin Marois1-Nov-17 5:43

Kevin Marois

1-Nov-17 5:43

Works great! Thanks Pete

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

Re: What's The Best Way To Do This?

Pete O'Hanlon1-Nov-17 5:59

Pete O'Hanlon

1-Nov-17 5:59

No problem. Glad I could help.

This space for rent

Re: What's The Best Way To Do This?

Nathan Minier1-Nov-17 1:36

Nathan Minier

1-Nov-17 1:36

Ah, the reason I like coding against interfaces instead of abstracts!

I've used this for getters before, but not setters, so that bit is a little up to you. The setter implementation isn't exactly tested.

public interface ISetting
{
   object SettingValue { get; set; }
   object MinValue { get; set; }
   object MaxValue { get; set; }
   string Key { get; set; }
   string Description { get; set; }
}

public class Setting<T> : ISetting
{
   public T SettingValue { get; set; }
   public T MinValue { get; set; }
   public T MaxValue { get; set; }
   public string Key { get; set; }
   public string Description { get; set; }

   object ISetting.SettingValue
   {
      get => SettingValue;
      set {
         var xlate = value as T;
         if(xlate != null)
         {
            SettingValue = t;
         }
         else
         {
            throw new Exception($"Invalid type assignment for Setting<{typeof(T)}>.SettingValue ");
         }
      }
   }

   object ISetting.MinValue 
   {
      get => MinValue;
      set {
         var xlate = value as T;
         if(xlate != null)
         {
            MinValue = t;
         }
         else
         {
            throw new Exception($"Invalid type assignment for Setting<{typeof(T)}>.MinValue");
         }
      }
   }

   object ISetting.MaxValue  
   {
      get => MaxValue;
      set {
         var xlate = value as T;
         if(xlate != null)
         {
            MaxValue= t;
         }
         else
         {
            throw new Exception($"Invalid type assignment for Setting<{typeof(T)}>.MaxValue");
         }
      }
   }
}

public List<ISetting> MySettings { get; set; }

"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli

Re: What's The Best Way To Do This?

Sascha Lefèvre1-Nov-17 2:01

Sascha Lefèvre

1-Nov-17 2:01

var xlate = value as T;

This won't work with his struct types. Have to use is or .GetType() and then a hard cast to T.

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

Re: What's The Best Way To Do This?

Nathan Minier1-Nov-17 2:34

Nathan Minier

1-Nov-17 2:34

Thanks, I just threw the setter portion together without much thought or coffee; it's not in my usual use case.

"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli

Re: What's The Best Way To Do This?

Eddy Vluggen1-Nov-17 10:19

Eddy Vluggen

1-Nov-17 10:19

Kevin Marois wrote:

Anyone have a better idea?

The Newtonsoft serializer has no problems with that stucture. Does it have to be XML? And if so, what advantages do you expect from it versus JSON?

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: What's The Best Way To Do This?

Wendelius1-Nov-17 10:51

Wendelius

1-Nov-17 10:51

Not sure if I'm looking this correctly, but it seems that you only have key/value pairs perhaps with categorization.

So if the goal is only to let the user edit the values in UI and save them, why not define a data table and load/save it in order to persist the changes. For example, have a look at DataTable.ReadXml Method (String) (System.Data)

Next generics Problem

Kevin Marois31-Oct-17 6:03

Kevin Marois

31-Oct-17 6:03

See my previous post

Now in the base class I want to add a method that return all Data Types that match the generic type:

// Get back all Data Types that match the generic type
public List<DataType<T>> GetTypes(T typeToGet)
{
    return DataTypes.Where(x => x.ConvestionType == typeToGet).ToList();
}

but this fails to compile on the "x.ConvestionType == typeToGet".

The error is "Operator '==' cannot be applied to operands of type 'T' and 'T'".

Not sure why this doesn't work. The 'typeToGet' param is of the same type as the class. What's wrong here?

Thanks!

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

Re: Next generics Problem

harold aptroot31-Oct-17 6:11

harold aptroot

31-Oct-17 6:11

Yes you cannot use == on instances of fully generic types. == may not exist for all value types for example, and even if it did, it would exist in a way that is not useful in the context of generics.

For example,

static bool equals<T>(T a, T b)
{
    return a == b;
}

This doesn't work either. But this does: (using fairly rare syntax to constraint T to be a reference type, will use reference-equality regardless of how appropriate that is)

static bool equals<T>(T a, T b) where T : class
{
    return a == b;
}

Other methods of comparison may be more suitable, for example:

static bool equals<T>(T a, T b)
{
    return EqualityComparer<T>.Default.Equals(a, b);
}

Re: Next generics Problem

Kevin Marois31-Oct-17 6:25

Kevin Marois

31-Oct-17 6:25

Thanks! Ya learnt me somethin!

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

How To Make This Generic

Kevin Marois31-Oct-17 5:02

Kevin Marois

31-Oct-17 5:02

I'm trying to create a generic abstract class:

The base class:

public abstract class DotNetlTypeConverterBase<T>
{
    private List<DataType<T>> _dataTypes;
    public List<DataType<T>> DataTypes
    {
        get { return _dataTypes; }
        private set { _dataTypes = value; }
    }

    public DotNetlTypeConverterBase()
    {
        DataTypes = new List<DataType<T>>();
        Load();
    }

    protected abstract void Load();

    public class DataType<T>
    {
        public DotNetTypes DotNetType { get; private set; }
        public T ConvestionType { get; private set; }

        public DataType(DotNetTypes dotNetType, T convestionType)
        {
            DotNetType = dotNetType;
            ConvestionType = convestionType;
        }
    }
}

A subclass:

public class DotNetToSqlTypeConverter<SqlDbType> : DotNetlTypeConverterBase<SqlDbType>
{
    protected override void Load()
    {
        DataTypes.Add(new DataType<SqlDbType>(DotNetTypes.Short, SqlDbType.SmallInt));
        DataTypes.Add(new DataType<SqlDbType>(DotNetTypes.Double, SqlDbType.Double));
    }
}

In the subclass I get a compile error on second param to the ctor of DataType. The word "SqlDbType" is erroring, yet that's the type I've specified.

The error is "'SqlDbType' is a type parameter, which is not valid in the given context"

What am i doing wrong here?

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

modified 31-Oct-17 11:24am.

Re: How To Make This Generic

Sascha Lefèvre31-Oct-17 5:43

Sascha Lefèvre

31-Oct-17 5:43

This:

public class DotNetToSqlTypeConverter<SqlDbType>

..overrides the meaning of SqlDbType as the enumeration type - it's now a generic type name, like T in the base class.

You could fix that theoretically by doing this:

public class DotNetToSqlTypeConverter<SqlDbType> : DotNetlTypeConverterBase<System.Data.SqlDbType>
{
    protected override void Load()
    {
        DataTypes.Add(new DataType<System.Data.SqlDbType>(DotNetTypes.Short, System.Data.SqlDbType.SmallInt));
        DataTypes.Add(new DataType<System.Data.SqlDbType>(DotNetTypes.Double, System.Data.SqlDbType.Float));
    }
}

But you don't actually want that. Instead change the class to being non-generic:

//                                 vvv
public class DotNetToSqlTypeConverter : DotNetlTypeConverterBase<SqlDbType>
{
    protected override void Load()
    {
        DataTypes.Add(new DataType<SqlDbType>(DotNetTypes.Short, SqlDbType.SmallInt));
        DataTypes.Add(new DataType<SqlDbType>(DotNetTypes.Double, SqlDbType.Float));
    }
}

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

Re: How To Make This Generic

Kevin Marois31-Oct-17 5:55

Kevin Marois

31-Oct-17 5:55

That did it!

I'm getting old. Totally missed that Poke tongue | ;-P

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

WPF assembly in C#

Benjamin Bruno30-Oct-17 19:36

Benjamin Bruno

30-Oct-17 19:36

I want to create a WPF dll( assembly),so that I can use it in some other C# or VC++ application.
Please help.

Re: WPF assembly in C#

Mycroft Holmes30-Oct-17 20:30

Mycroft Holmes

30-Oct-17 20:30

Why does it have to be a WPF dll, the only reason to use WPF is for the UI, probably not valid to use such a DLL in c++.

Otherwise just create a WPF library application.

Never underestimate the power of human stupidity
RAH

Re: WPF assembly in C#

Pete O'Hanlon30-Oct-17 20:31

Pete O'Hanlon

30-Oct-17 20:31

You will have to describe what you want your assembly to contain before you get a definitive answer. There are a number of assumptions that I could make about what you want here that possibly wouldn't be valid. For instance, do you want it to contain WPF screens? Does it just need to be the data and business logic?

This space for rent

Re: WPF assembly in C#

OriginalGriff30-Oct-17 20:37

OriginalGriff

30-Oct-17 20:37

Open VS.
Either open your existing solution and use the Solution Explorer pane to add a new project, or create a new project.
Select the "Visual C#" ... "Windows Desktop" project types from the menu on the left of the New Project dialog.
In the middle panel, select "WPF User Control Library"
Give it an appropriate name.
Press OK.

Now you can create the controls and code for your Assembly.

Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!

Re: WPF assembly in C#

Gerry Schmitz31-Oct-17 12:17

Gerry Schmitz

31-Oct-17 12:17

I want a cup of coffee so I can drink it...

Please help.

"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal

Re: WPF assembly in C#

peterkmx2-Nov-17 6:29

peterkmx

2-Nov-17 6:29

here it is ... Java | [Coffee]

Enum of C# Data Types - byte[] and char[]

Kevin Marois30-Oct-17 12:30

Kevin Marois

30-Oct-17 12:30

I'm working on a type converter for .Net to Sql and .Net to OleDb.

First, I create a class called DataType:

public class DataType
{
    public DotNetTypes? DotNetType { get; private set; }
    public SqlDbType? SqlDbType { get; private set; }
    public OleDbType? OleDbType { get; private set; }

    public DataType(DotNetTypes? dotNetType, SqlDbType? sqlDbType, OleDbType? oleDbType)
    {
        DotNetType = dotNetType;
        SqlDbType = sqlDbType;
        OleDbType = oleDbType;
    }
}

Next I load it like this:

private static List<DataType> DataTypes;

static DataTypeConversion()
{
    Load();
}

private static void Load()
{
    DataTypes = new List<DataType>
    {
        new DataType(DotNetTypes.Short, SqlDbType.SmallInt, null),
        new DataType(DotNetTypes.Int32, SqlDbType.Int, null),
        new DataType(DotNetTypes.Int64, SqlDbType.BigInt, null),
        new DataType(DotNetTypes.Boolean, SqlDbType.Bit, null),
        new DataType(DotNetTypes.Double, SqlDbType.Float, null),
        new DataType(DotNetTypes.Float, SqlDbType.Real, null),
        new DataType(DotNetTypes.Guid, SqlDbType.UniqueIdentifier, null),
        new DataType(DotNetTypes.Byte, SqlDbType.TinyInt, null),
        new DataType(DotNetTypes.DataTable, SqlDbType.Structured, null),

        new DataType(DotNetTypes.DateTime, SqlDbType.DateTime, null),
        new DataType(DotNetTypes.DateTime, SqlDbType.SmallDateTime, null),
        new DataType(DotNetTypes.DateTime, SqlDbType.Date, null),
        new DataType(DotNetTypes.DateTime, SqlDbType.Time, null),
        new DataType(DotNetTypes.DateTime, SqlDbType.DateTime2, null),

        new DataType(DotNetTypes.DateTimeOffset, SqlDbType.DateTimeOffset, null),

        new DataType(DotNetTypes.Object, SqlDbType.Variant, null),
        new DataType(DotNetTypes.Object, SqlDbType.Udt, null),

        new DataType(DotNetTypes.Decimal, SqlDbType.Decimal, null),
        new DataType(DotNetTypes.Decimal, SqlDbType.Money, null),
        new DataType(DotNetTypes.Decimal, SqlDbType.SmallMoney, null),

        new DataType(DotNetTypes.Byte, SqlDbType.Binary, null),
        new DataType(DotNetTypes.Byte, SqlDbType.Image, null),
        new DataType(DotNetTypes.Byte, SqlDbType.VarBinary, null),
        new DataType(DotNetTypes.Byte, SqlDbType.Timestamp, null),

        new DataType(DotNetTypes.String, SqlDbType.NVarChar, null),
        new DataType(DotNetTypes.String, SqlDbType.VarChar, null),
        new DataType(DotNetTypes.String, SqlDbType.Char, null),
        new DataType(DotNetTypes.String, SqlDbType.NChar, null),
        new DataType(DotNetTypes.String, SqlDbType.NText, null),
        new DataType(DotNetTypes.String, SqlDbType.Text, null),
        new DataType(DotNetTypes.String, SqlDbType.Xml, null)
    };
}

To do this I created an enum called DotNetTypes:

public enum DotNetTypes
{
    @Unknown,
    @Short,
    @Boolean,
    @Byte,
    @Char,
    @DateTime,
    @DateTimeOffset,
    @Decimal,
    @Double,
    @Int32,
    @Int16,
    @Int64,
    @Float,
    @Object,
    @SByte,
    @Single,
    @String,
    @UInt16,
    @UInt32,
    @UInt64,
    @Guid,
    @DataTable
}

Notice that in the Load method I have

new DataType(DotNetTypes.Byte, SqlDbType.Binary, null),
new DataType(DotNetTypes.Byte, SqlDbType.Image, null),
new DataType(DotNetTypes.Byte, SqlDbType.VarBinary, null),
new DataType(DotNetTypes.Byte, SqlDbType.Timestamp, null),

The problem is that these should be byte arrays, not byte. So what is the syntax for this in my DotNetTypes enum?

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.

Re: Enum of C# Data Types - byte[] and char[]

Sascha Lefèvre30-Oct-17 14:06

Sascha Lefèvre

30-Oct-17 14:06

DotNetTypes.ByteArray ? Confused | :confused:

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

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