C语言动态链接库编程

1、C语言动态链接库编程VB6中引用VC6编写的.DLL函数进行屏幕绘图一、动态链接库的基本概念动态链接库（DynamicLinkLibrary，简称DLL）是由函数对象以及资源组成的二进制库文件，此库文件能同时被多个进程或者应用程序使用。2.添加(.cpp)文件到工程(Graph.cpp)3.p#ifndefWIN32GDI_API#defineWIN32GDI_API_declspec(dllexport)#defineEXCexternC#defineCALL_stdcall#endif#include#include#includetypedefstruct_tagSIZE2Iintwid

2、th;intheight;SIZE2I;typedefstruct_tagCOLOR4Uunsignedcharb;unsignedcharg;unsignedcharr;unsignedchara;COLOR4U;typedefstruct_tagCOLOR4Iintb;intg;intr;inta;COLOR4I;HDC_g_hDC;COLOR4U*_g_bitmap;COLOR4I_g_ftcolor;COLOR4I_g_bkcolor;SIZE2I_g_size=300,200;SIZE2I_g_oldsize=-100,-100;int_g_win_test=0;EXCWIN32GD

3、I_APIvoidCALLSetGraphicsDC(HDCshdc)_g_hDC=shdc;EXCWIN32GDI_APIvoidCALLInitGraph(intw,inth)if(w200)w=200;if(h255)number=255;if(number0)number=0;returnnumber;COLOR4IGetColor4i(intr,intg,intb,inta)COLOR4Icr=b,g,r,a;returncr;EXCWIN32GDI_APIvoidCALLSetColor(intr,intg,intb)r=TestNumber(r);g=TestNumber(g);

4、b=TestNumber(b);_g_ftcolor=GetColor4i(r,g,b,0);EXCWIN32GDI_APIvoidCALLSetBackColor(intr,intg,intb)r=TestNumber(r);g=TestNumber(g);b=TestNumber(b);_g_bkcolor=GetColor4i(r,g,b,0);EXCWIN32GDI_APIvoidCALLFlush()HBITMAP_cgl_bitmap=CreateBitmap(_g_size.width,_g_size.height,1,32,_g_bitmap);HBRUSHhb=CreateP

5、atternBrush(_cgl_bitmap);SelectObject(_g_hDC,hb);Rectangle(_g_hDC,10,10,_g_size.width-25,_g_size.height-50);DeleteObject(hb);DeleteObject(_cgl_bitmap);COLOR4UGetColor4u(COLOR4Ici)COLOR4Uti=ci.b,ci.g,ci.r,ci.a;returnti;EXCWIN32GDI_APIvoidCALLClear()intlen,i;COLOR4Utm=GetColor4u(_g_bkcolor);len=_g_siz

6、e.width*_g_size.height;for(i=0;i=0&x=0&y=abs(y2-y1)len=abs(x2-x1);elselen=abs(y2-y1);SetPixel2i(int)x,(int)y);dx=(float)(x2-x1)/len;dy=(float)(y2-y1)/len;for(i=1;i=len;i+)x+=dx;y+=dy;SetPixel2i(int)x,(int)y);5.在Graph.def文件中编写Lib(*疝1)入口函数名字的源文件LIBRARYGraphEXPORTSSetGraphicsDCInitGraphSetColorSetBackColorFlushClearSetPixel2iLin