为啥会一直刷新WM_PAINT函数？求解啊

漠水

自制一个输出函数，调用后为啥会一直刷新

#include<windows.h>
#include "strsafe.h"
LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT("my windows");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;

wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = WndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon(NULL,IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL,IDC_ARROW);
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = szAppName;

if(!RegisterClass(&wndclass))
{
MessageBox(NULL,TEXT(""),szAppName,MB_OK);
return 0;

}

hwnd = CreateWindow(szAppName,
TEXT("这才是正文"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL);
ShowWindow(hwnd, iCmdShow);

UpdateWindow(hwnd);

while(GetMessage(&msg,NULL,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);

}

return msg.wParam;

}

int print(HWND hwnd ,int ch,TCHAR cha[])
{

HDC hdc;
int x,y;
TCHAR szBuffer[128]; //字符数组 
size_t TT; //字符数组长度
TEXTMETRIC tm; // 字符的尺寸 TEXTMETRIC 结构记录当前设备环境中有关字体的各种信息

hdc = GetDC(hwnd);
GetTextMetrics(hdc,&tm); 
x = tm.tmAveCharWidth; //字符的尺寸宽度
y = tm.tmHeight +tm.tmExternalLeading; //字符的尺寸高度+字符的尺寸上下间距

StringCchPrintf(szBuffer,128,cha); //
StringCchLength(szBuffer,128,&TT); //

TextOut(hdc,0,ch*y,szBuffer,TT); 

ReleaseDC(hwnd,hdc); //

ch = ch + 1; 
return ch;



}


LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{

int ch = 0;


TCHAR szBuffer[12] = TEXT("HELLO WORLD"); 

switch(message)
{


case WM_PAINT:
//s print(HWND hwnd ,s ch,TCHAR cha[])
ch = print(hwnd,ch,szBuffer);
ch = print(hwnd,ch,szBuffer);

return 0;


case WM_DESTROY:
PostQuitMessage(0);
return 0;

}

return DefWindowProc(hwnd,message,wParam,lParam);


}

向往青莲

http://baike.baidu.com/link?url=DMiXg_-CIhKpcW3y74wwJIqHtdSZ4t2-ZAud-7zxXdw0cXegeuV6ceBIolp5NwhyDZEAP5omCLuN4ZHPU4xieq

漠水

向往青莲 发表于 2015-1-8 10:48
http://baike.baidu.com/link?url=DMiXg_-CIhKpcW3y74wwJIqHtdSZ4t2-ZAud-7zxXdw0cXegeuV6ceBIolp5NwhyDZEA ...

原来是因为WM_PAINT函数必须以hdc = BeginPaint(hwnd,&ps);这语句作为开始
以EndPaint(hwnd,&ps);作为结束
不能用GetDC(hwnd)和Release(hwnd,hdc)作为开始和结束啊

freeparty

我来看看{:1_1:}

air-C

围观学习

智商是硬伤

{:7_147:}