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I have an apllication that has been written as a dos based command driven interface in c code. &nbsp;I am trying to redesign the interface within the .net environment. &nbsp;I have created a dll with the existing c source code and have exported the necessary functions that I need to interact with the interface. &nbsp;I was using c#.net for testing if I could pass between the dll and the new interface. &nbsp;Integers are passing find but I am having problems with the strings as c defines these as chars and c++ c#.net refer to them as string types. &nbsp;I was hope to pass these as values, but maybe it would be possible using pointers?<br />
<br />
Below shows some of the coding I have tried in c#.net.<br />
<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;public class Win32<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[DllImport(&quot;Caspian1.dll&quot;)<wbr />]<br />
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;public static extern string test();<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;}<br />
<br />
<br />
textBox4.Text = Win32.test();<br />
<br />
<br />
Any advice at all would be greatly appreciated.<br />

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I have an apllication that has been written as a dos based command driven interface in c code.  I am trying to redesign the interface within the .net environment.  I have created a dll with the existing c source code and have exported the necessary functions that I need to interact with the interface.  I was using c#.net for testing if I could pass between the dll and the new interface.  Integers are passing find but I am having problems with the strings as c defines these as chars and c++ c#.net refer to them as string types.  I was hope to pass these as values, but maybe it would be possible using pointers?

Below shows some of the coding I have tried in c#.net.

	public class Win32
	{
		
		[DllImport("Caspian1.dll")]
		public static extern string test();
               }


textBox4.Text = Win32.test();


Any advice at all would be greatly appreciated.


Working with C dll

C is a general-purpose, imperative computer programming language, supporting structured programming, lexical variable scope and recursion, while a static type system prevents many unintended operations. By design, C provides constructs that map efficiently to typical machine instructions, so it has found lasting use in applications that had formerly been coded in assembly language, including operating systems as well as various application software for computers ranging from supercomputers to embedded systems. It is distinct from C++ (which has its roots in C) and C#, and many later languages have borrowed directly or indirectly from C.