等效于C＃中VB6中的字符串* 10

Question

I have import an unmanageable .dll to my project. It's no any document left and the original working code is in VB6. so I try to make C# code equivalent to VB6 as same as possible.

PROBLEM

I don't know how to convert following code to C#...

Dim ATQ As String * 10
Dim Uid As String * 10
Dim MultiTag As String * 10

NOTE

Q: some users ask me that do you really need string fixed length?

A: I already try string in c# but there are no result update to these variable. So, I think input signature for the dllImport function might be wrong. So, I want to make it as same as VB6 did because I didn't know exactly what should be the right signature.

TRIAL & ERROR

I tried all of this but it's not working (still no result update to these variable)

Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString ATQ = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(10)
Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString Uid = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(10)
Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString MultiTag = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(10)

Answer 1

You can use Microsoft.VisualBasic.Compatibility :

using Microsoft.VisualBasic.Compatibility;

var ATQ = new VB6.FixedLengthString(10);
var Uid = new VB6.FixedLengthString(10);
var MultiTag = new VB6.FixedLengthString(10);

But it's marked as obsolete and specifically not supported for 64-bit processes , so write your own that replicates the functionality, which is to truncate on setting long values and padding right with spaces for short values. It also sets an "uninitialised" value, like above, to nulls.

Sample code from LinqPad (which I can't get to allow using Microsoft.VisualBasic.Compatibility I think because it is marked obsolete, but I have no proof of that):

var U = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(5);
var S = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(5,"Test");
var L = new Microsoft.VisualBasic.Compatibility.VB6.FixedLengthString(5,"Testing");
Func<string,string> p0=(s)=>"\""+s.Replace("\0","\\0")+"\"";
p0(U.Value).Dump();
p0(S.Value).Dump();
p0(L.Value).Dump();
U.Value="Test";
p0(U.Value).Dump();
U.Value="Testing";
p0(U.Value).Dump();

which has this output:

"\\0\\0\\0\\0\\0"
"Test "
"Testi"
"Test "
"Testi"

Answer 2

string ATQ;
string Uid;
string MultiTag;

One difference is that, in VB6, I believe the String * 10 syntax may create fixed-size strings. If that's the case, then the padding behavior may be different.