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c#pinvokemarshallingdllimportstructlayout

Does "DefaultCharSetAttribute" apply to "StructLayoutAttribute.CharSet" too?

C# default platform invoke uses ANSI marshalling both for method parameters and struct fields strings.

System.Runtime.InteropServices contains an attribute "DefaultCharset" to change it to Unicode.

From MSDN: "Apply the DefaultCharSetAttribute attribute at the assembly level or module level to set the CharSet value for any call to DllImportAttribute that does not include a CharSet named argument specified by the user."

My question is: does this attribute set the default for "StructLayoutAttribute.CharSet" too?

Thanks!

Solution

  • Just try it:

    using System;
using System.Runtime.InteropServices;

[module: DefaultCharSet(CharSet.Unicode)]

class Program {
    static void Main(string[] args) {
        var sla = typeof(Foo).StructLayoutAttribute;
        Console.WriteLine(sla.CharSet);
        Console.ReadLine();
    }
}

struct Foo { };

    Output:

      Unicode

    So yes.