win7+vs2010 making and calling DLLs

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Well hum ~ to help the teacher before the module, do not have to do = =.

For nearly 10 days, the results ran for 13 minutes.

Others, second level, even the speed of the millisecond level ....

Hey....

Kneel ing,2000+ X 2000+ matrix, multiply, multiply, transpose, reverse, a series of operations,

Furthermore, the multiplication must be carried out at least 40+ times, and the inverse is 40+ times,

This is how the second level results in = =:

Or, they are not calculated by the matrix at all.

Oh, I don't think so.

Teacher, is made in C #, then I will make this function module DLL, give him, tell him parameters and return.

Words, I wouldn't do dll, to show shame ing

As a result, a variety of search and test, finally understand.

By the right, my environment is WIN7 + VS2010

1. Generating DLL files

Well, first, open VS2010 to create a new WIN32 project, name Max_2 (of course, what you want to call it):

Pop-Up dialog box, click Next

Then select the DLL and click on the Empty project and select Finish:

Then, right-click on the project name, and select Add-new item:

Then, look for the. cpp file, enter the file name, and create:

Then, fill in your code, here I will compare two number size for example:

Fill in the. cpp: (note __declspec and __cdecl are all two _)

extern "C" __declspec (dllexport) int __cdecl max (int a, int b) {Returna > B? a:b;}

--Here the extern "C" is to prevent the following may occur: Can load DLL file, but cannot find the function of the case.

extern "C" means: Tell the C + + compiler This function, C-style compilation. This mainly depends on how you call, with C-style calls or C + + style calls. (You can also see this http://blog.csdn.net/zhongjling/article/details/8088664.)

__declspec (dllexport) is the necessary thing to generate the DLL, and if not, you can replace it with a new. def file.

The--__cdecl effect is to specify that the function call rule in the VC is __cdecl. Because of the VC environment, the default call rule is __cdecl, so you can also not write. Of course, in addition to the __cdecl there are conventions called WIN32 API functions __stdcall, the performance requirements are very high in the case of __fastcall.

These details are not described in detail and can be seen in http://blog.csdn.net/kesalin/article/details/2447368

And then the size of the function, type, name, the content will not need to say it? (Focus on making DLLs)

Here, I choose to make the DLL of release,

Choose Build-and-Configure manager:

Then, in the active solution configuration, select Release:

Click Close, and then build the solution.

Then, under the generated file root directory, locate the release folder,

You can see the DLL file when you open it:

Ok,dll file generated successfully!

2. Calling the DLL

Next, it's how to downgrade the DLL in VS.

Create a new WIN32 console application (deselect Build Solution):

Then, in the pop-up window, click Next, then select Console application, empty project:

As with the build, create a new. cpp file,

Then fill in the inside:

#include <Windows.h> #include <stdio.h>typedef int (__cdecl *findmax) (int a, int b); int main () {Findmax FM Ax Hmodule hlib;hlib = LoadLibrary (TEXT ("Max_2.dll")), Fmax = (Findmax) GetProcAddress (hlib, "Max"), if (hlib = = NULL) {pri NTF ("DLL get failed \ n");} if (Fmax = = NULL) {printf ("function get failed \ n");} int A,b;while (scanf ("%d%d", &a,&b)!=eof) {if (!a &&!b) break;printf ("%d and%d, larger:%d\n", A,b,fmax (A, B ));} System ("pause"); return 0;}

Of course, put your DLL in the same directory as the SLN.

(What ' s the sln?) In short, you open the VS2010, select Open Project, and then you want to select the file. )

To build a solution, run:

Can Yo ~

There are some differences under the. cpp file:

For example, for hmodule, this can also be hinstance and HWND:

You can see http://blog.csdn.net/zhchongyao/article/details/6216659.

Of course, you can also call a DLL in a DLL:

Method (The function compares three number sizes):

#include <windows.h>typedef int (__cdecl *findmax) (int a, int b), extern "C" __declspec (dllexport) int __cdecl th _max (int A, int b, int c) {Findmax Fmax; HInstance Hlib;hlib = LoadLibrary (TEXT ("Max_2.dll")), Fmax = (Findmax) GetProcAddress (hlib, "Max"), Return Fmax (Fmax (A , b), c);}

However, to invoke this DLL, you must also place the DLL and the Max_2.dll in the same directory as the SLN.

Indispensable Yo ~

Well, for DLL making and use that's it ~

See u~

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win7+vs2010 making and calling DLLs