using the IConvertible interface:

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using the IConvertible interface:
i basically want to convert a "TypeA" to boolean<br/>TypeA is very simple, all it is is this
struct TypeA <br/>    {<br/>        public int value;<br/>    }
 
<br/>so i gave it the IConvertible interface,<br/>and visual studio added a bunch of "IConvertible Members"
among them "ToBoolean"
struct TypeA : IConvertible <br/>    {<br/>        public int value;<br/> <br/> public bool ToBoolean(IFormatProvider provider)<br/>        {<br/>        }<br/> . . .<br/>    }
= = = = = = = = = = =  = = = = =
<br/>My problem is i dont know what to put in the Toboolean method!
I have this:<br/>TypeA a; a.value = 42;
i now just want to go like this:<br/>bool b;<br/>b = Convert.ToBoolean(a);
<br/>I want ToBoolean to do this:<br/>if value of a > 0, return true<br/>else return false
<br/>thats it!
<br/>i tried things, but nothings working<br/>(i guess i have to stick to this signature)<br/> public bool ToBoolean(IFormatProvider provider)<br/>        {<br/>        }
i tried if a.value > 0 return true.<br/>But it doesnt recognize a
Heres the whole code:
 
<pre lang=x-aspx>//**********************************
using System;
using System.Collections.Generic;
using System.Text;

namespace myChap01Less04Proj01
{
class Program
{
static void Main(string[] args)
{
TypeA a;
a = 42;
bool b;
//convert using ToBoolean
b = Convert.ToBoolean(a);
Console.WriteLine("b took in a TypeA, and is now: {0}", b.ToString());
}


}


// i think this can go on a separate file
struct TypeA : IConvertible
{
public int value;
//allows implicit conv from an int
public static implicit operator TypeA(int _i)
{
TypeA a;
a.value = _i;
return a;
}

//allows explicit conv to an int
//so without this you cant do explicit??
public static explicit operator int(TypeA _a)
{
return _a.value;
}

//provides string conversion (the ToString) to avoid boxing
public override string ToString()
{
return this.value.ToString();
}

//***********************************************************
//***********************************************************
// automagically added stuff by vs
//***********************************************************
//***********************************************************

#region IConvertible Members

public TypeCode GetTypeCode()
{
throw new Exception("The method or operation is not implemented.");
}

//public bool ToBoolean(IFormatProvider provider)
public bool ToBoolean(IFormatProvider provider)
{
//throw new Exception("The method or operation is not implemented.");
if (a.value > 0)
return true;
return false;
}

public byte ToByte(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public char ToChar(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public DateTime ToDateTime(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public decimal ToDecimal(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public double ToDouble(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public short ToInt16(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public int ToInt32(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public long ToInt64(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public sbyte ToSByte(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public float ToSingle(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public string ToString(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public object ToType(Type conversionType, IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public ushort ToUInt16(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public uint ToUInt32(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

public ulong ToUInt64(IFormatProvider provider)
{
throw new Exception("The method or operation is not implemented.");
}

#endregion
}
}
[/code]
 

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