I want to do this, but getting this error:
Error 1 Cannot define a new extension method because the compiler required type 'System.Runtime.CompilerServices.ExtensionAttribute' cannot be found. Are you missing a reference to System.Core.dll? [snipped some path stuff]
I have seen some answers here that says, you have to define this attribute yourself.
How do I do that?
EDIT : This is what I have:
[AttributeUsage ( AttributeTargets.Assembly | AttributeTargets.Class | AttributeTargets.Method )]
public sealed class ExtensionAttribute : Attribute
{
public static int MeasureDisplayStringWidth ( this Graphics graphics, string text )
{
}
}
Like so:
// you need this once (only), and it must be in this namespace
namespace System.Runtime.CompilerServices
{
[AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Class
| AttributeTargets.Method)]
public sealed class ExtensionAttribute : Attribute {}
}
// you can have as many of these as you like, in any namespaces
public static class MyExtensionMethods {
public static int MeasureDisplayStringWidth (
this Graphics graphics, string text )
{
/* ... */
}
}
Alternatively; just add a reference to LINQBridge .
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