string to ref string error ??[Resolved]

[Pirate]

This is weird . Below, the method signature is marked as ByRef . I exported this class to dll file . It works fine in VB. In C# , it gives me two strange errors .They say : Argument '1': cannot convert from 'string' to 'ref string'
and
Argument '2': cannot convert from 'string' to 'ref string'

Public Shared Function FindFile(ByRef RootPath As String, ByRef FileName As String) As String

I used it like this :

MessageBox.Show(FindFileViaAPI.FileClass.FindFile("c:\\" ,"setup.exe"));

Anyone knows why ?

[Sgt-Peppa]

Have you tryed to this?:

MessageBox.Show(FindFileViaAPI.FileClass.FindFile(@"c:\\" ,"setup.exe"));

Hope thats it,

Stephan

[dynamic_sysop]

have you tried adding ref, eg:

MessageBox.Show(FindFileViaAPI.FileClass.FindFile([COLOR=blue]ref[/color] "c:\\" ,[COLOR=blue]ref[/color] "setup.exe"));

[DevGrp]

What dynamic_sysop said. See, in C# you have to use the ref keyword when passing in a value type variable by reference. Its a little different with reference types.

[Pirate]

Originally posted by Sgt-Peppa
Have you tryed to this?:

MessageBox.Show(FindFileViaAPI.FileClass.FindFile(@"c:\\" ,"setup.exe"));

Stephan

The same error arised again .

and

When I tried what dynamic_sysop said , it gives this error :
A ref or out argument must be an lvalue

[DevGrp]

Try this

string _rootPath = @"C:\";
string _fileName = "setup.exe";

MessageBox.Show(FindFileViaAPI.FileClass.FindFile(ref _rootPath, ref _fileName));

[Pirate]

Thanks , this works well . Do you know why ?

[DevGrp]

As to what the error said, you have to use an lvalue.

[Pirate]

Cool .