IntPtr is a .NET Framework platform-specific type that is used to represent a pointer or a handle.
IntPtr is a .NET Framework platform-specific type that is used to represent a pointer or a handle.
Questions tagged [intptr]
296 questions
4
votes
2 answers
Pointer to function for unmanaged code in C#
I have a dll which accepts a struct that contains a pointer to a function to do a callback.
How can I get an IntPtr to a function of my application to build the struct?
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public…
Sergi
- 85
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- 4
4
votes
1 answer
Passing strings to c dll from C#
I have some trouble using a c dll in a c# application. The function which gives me an error is defined in the header file of the dll like this:
int __stdcall DDC_CreateFilePropertyString (DDCFileHandle file,
…
Devkev
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4
votes
2 answers
How to convert a Bitmap Image to IntPtr in C#?
I made this from an example i saw, it never threw any error, but the image is displayed as grey.
Is there a better way to do this?
private unsafe void menuItem7_Click(object sender, EventArgs e)
{
var settings =…
Martin Ongtangco
3
votes
1 answer
How to "fill" an IntPtr parameter with a float value?
I am using dllImport to use a C library in C# .NET. One of the methods in this library uses data type void* as parameter. I found out, that I can use the data type IntPtr in C# matching the void*.
Now I simply don't know how to set the value of…
Simone Frank
3
votes
1 answer
Convert IntPtr to int* in C#?
I have a C++ DLL returning an int* to a C# program. The problem is the int* in C# remains null after the assignment.
When I assign the C++ result to an IntPtr, I get a correct non-null value. However any attempt to convert this to an int* results…
user20493
- 5,704
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3
votes
2 answers
Convert double[,] to IntPtr C#
I need to convert a double array in c# to an IntPtr to properly send it to my c DLL. I have successfully been able to convert from IntPtr to double[,] using the method from this answer. Ive also found another answer that is close to what I need but…
6seven8nine
- 43
- 4
3
votes
0 answers
Marshalling a variable from int to struct in 64X
When my application is running on x86 the program works fine. When I run it on x64, the Access Violation exception occurs. Exception details mentioned below.
"System.AccessViolationException: 'Attempted to read or write protected memory. This is…
Visithra Venkatesan
- 31
- 1
3
votes
3 answers
How can I get IntPtr pointer from object
I'm working on a finger-print device, the manufacture (Upek) gave me a c++ BSAPI.dll so I need to use wrappers to get this to work in .net.
I'm able to work with it all from in-memory, I could grab and match the finger prints.
Now I'm stuck trying…
Ezi
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3
votes
1 answer
IntPtr causing memory leak?
This function is in a loop. When I run the program, the line with IntPtr is giving me memory problems, I've put delete[], but it still doesn't solve the memory problem, can anyone help please? thanks
void showImage(IplImage…
Qmage
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3
votes
1 answer
How to get byte[] from IntPtr in C#
I want to pass a IntPtr to a method takes a byte[] Parameter in c#. Is that possible and if it is possible how can I do that?
thx
user594810
- 149
- 4
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3
votes
1 answer
Is default(IntPtr) legal in an extern function?
Let's say I have the following signature:
static extern void External(int foo, IntPtr bar);
I want to make it use defaults:
static extern void External(int foo = 10, IntPtr bar = default(IntPtr));
Is this valid? In C++, I would use the pointer to…
Lazlo
- 8,518
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3
votes
1 answer
Interop question about passing a struct by ref, null pointer and IntPtr
Colleagues,
Preamble. My question is more about best practices. I know one workaround. This is the first time I have to deal with interop in C#, at the same time I’ve written a fair amount of code in C and C++.
I need to invoke 2 times a…
Nick Alexeev
- 1,688
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3
votes
1 answer
How do I marshal a wstring * in C#?
I have a function in C++, _GetFileList, that I am trying to get to return a list/array of strings to C# code. I am not married to wstring * or any other type, this is just how the example I had found did it, but I am trying to get it to return a…
WWZee
- 494
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3
votes
2 answers
The new IntPtr.Add method - am I missing the point of the int?
Starting from FW 4.0, the IntPtr structure has the Add method:
public static IntPtr Add(
IntPtr pointer,
int offset
)
Which is great, as it's supposed to address all those questions on IntPtr math we have had (1, 2, probably more).
But why…
GSerg
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3
votes
1 answer
Do I need to release an IntPtr inside a callback?
I'm Marshalling data across C/C# boundary. I have the following structure:
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public struct Message
{
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]
public string From;
…
Eternal21
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