c++ dll in C# project

[danmoran]

Im trying to use an external DLL and extract data from the dll. my code is as follows:

myMethod should return a Zero "0". but when I run it I get an error message "vshost.exe has stopped working".

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        [DllImport("c:\\Program Files\\DHI\\Calibration\\muEpanet2.dll")]
        public static extern long myMethod (ref string F1, ref long F2, ref long F3);
 
 
        public Form1()
        {
            InitializeComponent();
        }
 
        private void button1_Click(object sender, EventArgs e)
        {
            long errorCode;
            string fileLocation = "c:\\base_zk-M1.res";
            long secondParameter = 13;
            long thirdParameter = 0;
 
 
            errorCode = myMethod (ref fileLocation, ref secondParameter, ref thirdParameter);
        }
 
    }

thanks so much for your help.

[tlhintoq]

TIP: When you first created your question you were asked to wrap your code with [code] tags.

It really does help a bunch. Look how much easier it is to read now that someone has done it for you. Its the button with a '#' on it.

More on tags. They're cool. Check'em out.

[danmoran]

I am trying to get a method out of a C++ dll in C#. Can anybody help me I can't extract the method myDll which takes 3 parameters (string, long, long). I get an error message "vshost.exe stopped working " Can anybody tell me what's wrong with the code below.

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        // here I call the external dll including its method MUEpanet_RES_Load2Mem_InitHeader
        [DllImport(@"c:\Program Files\DHI\Calibration\muEpanet2.dll")]
        private static extern long myDll(string F1, long F2, long F3);
 
        public Form1()
        {
            InitializeComponent();
        }
 
        private void button1_Click(object sender, EventArgs e)
        {
            long errorCode;
            string fileLocation = @"c:\list.xml";
            long secondParameter = 13;
            long thirdParameter = 0;
 
            errorCode = myDll(fileLocation, secondParameter, thirdParameter);
        }
    }
}

Thanks in advance.

[danmoran]

I have the following code in VBA I would like to convert the same code to C#. the VBA codes calls a c++ dll which includes method myMethod. Thanks so much for your help.

Private Declare Function myMethod Lib "c:\myDLL.dll" (ByVal F1 As String, ByVal F2 As Long, ByVal F3 As Long) As Long

[GaryTexmo]

I think this might be the same as [DllImport] in C#. Try googling that :)

Actually, your other thread uses it... so while I'm not 100% sure, that VB code looks to be the equivalent.

[danmoran]

@GaryTexmo
Yes, I google it and my code is OK... but I just can't see what it doesn't work.

[danmoran]

@danmoran
@GaryTexmo Yes, I google it and my code is OK... but I just can't see why my code doesn't give me the results I expect from the DLL

[tlhintoq]

Please don't TRIPLE-post your questions. It divides attempts to help you in an organized and cohesive manner. Your threads have been merged