VB.Net DLLImport

Question

我得到了一个PL/I DLL，我试图将该DLL导入到我的VB.Net应用程序中。 第一次尝试工作，但程序在几次呼叫后没有发表评论就退出了。 而且不可能从两个不同的线程调用这些函数两次。 我从paramone中的DLL中获得结果。任何想法为什么这不工作正确，以及如何让它工作？

<DllImport(("PLIDLL.dll"), CallingConvention:=CallingConvention.StdCall)> _ 
    Public Shared Sub MYFUNC(ByVal LogonString As String, _ 
           <MarshalAs(UnmanagedType.VBByRefStr)> ByRef paramone As String, _ 
           ByVal paramtwo As String) 
    End Sub 

如果有什么不清楚的地方请问。

问候林

PS：我已经尝试rerewrite的PL/I代码，以便它返回一个字符串，而不是为ByRef值。同样的问题。

在PLI小组：

MYFUNC: PROC(LOGONSTRING,PARAMONE,PARAMTWO) REORDER 
      OPTIONS(FROMALIEN NODESCRIPTOR 
        BYADDR LINKAGE(STDCALL)); 

      DEFAULT RANGE(*) STATIC; 


    DCL LOGONSTRING CHAR(30); 
    DCL PARAMONE CHAR(2033);    
    DCL PARAMTWO CHAR (5500);  

Answer 1

找到至少一个工作溶液。

Module NativeMethods 

<DllImport("kernel32.dll", SetLastError:=True)> _ 
    Public Function LoadLibrary(ByVal lpFileName As String) As IntPtr 
    End Function 

<DllImport("kernel32.dll", SetLastError:=True)> _ 
    Public Function GetProcAddress(ByVal hModule As IntPtr, ByVal procedureName As String) As IntPtr 
    End Function 

<DllImport("kernel32.dll", SetLastError:=True)> _ 
    Public Function FreeLibrary(ByVal hModule As IntPtr) As IntPtr 
    End Function 

End Module 


<UnmanagedFunctionPointer(CallingConvention.StdCall)> 
    Private Delegate Sub MYFUNC(ByVal LogonString As String, <MarshalAs(UnmanagedType.VBByRefStr)> ByRef PARAMONE As String, ByVal PARAMTWO As String) 

Public Shared Sub CallFunction(ByRef workingObject As PLIOBJECT) 
    Dim EntryPointer As IntPtr = NativeMethods.LoadLibrary("PLIDLL.dll") 
    Dim FunctionPointer As IntPtr = NativeMethods.GetProcAddress(EntryPointer, "MYFUNC") 
    Dim MyFUNC As MYFUNC= CType(Marshal.GetDelegateForFunctionPointer(FunctionPointer, GetType(MYFUNC)), MYFUNC) 
    MyFUNC(workingObject.Logonstring, workingObject.PARAMONE, workingObject.PARAMTWO) 
    Dim result As Boolean = NativeMethods.FreeLibrary(EntryPointer) 

End Sub