在Dev C++中编写了一个控制RFID读写器的程序，直接编译在DOS界面中可以正常运行
但是要求写界面，通过Windows API写了一个界面，把对应写串口放进按键事件中就出现了描述中的问题
w=WriteFile(hCom,message2,strlen(message2),&dwBytesWrite,NULL);
errors=GetLastError();
char buf1[10];
_ultoa(errors, buf1, 10);
fp=fopen("error.txt","w");
fprintf(fp,buf1);
fclose(fp);
if(!w)
{
MessageBox(NULL,"写串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
其中打开串口功能是成功的，也就是说在打开串口的按键事件中、writefile函数也是能成功写串口的
想要通过GetLastError来查看到底是为什么错了
但是看到的返回值是0，却讲没错
附全部代码：
#include
#include
#include <windows.h>
#include
#include
#include <stdio.h>
#include <stdlib.h>
using namespace std;
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
WNDCLASSEX wc;
HWND hwnd, hwndDT;
MSG msg;
RECT rect;
int dtWidth,dtHeight;
memset(&wc,0,sizeof(wc));
wc.cbSize = sizeof(WNDCLASSEX);
wc.lpfnWndProc = WndProc;
wc.hInstance = hInstance;
wc.hCursor = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wc.lpszClassName = "WindowClass";
wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
if(!RegisterClassEx(&wc)) {
MessageBox(NULL, "Window Registration Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);
return 0;
}
hwndDT=GetDesktopWindow(); //取桌面句柄
GetWindowRect(hwndDT,&rect); //取桌面范围
dtWidth=rect.right-rect.left; //桌面宽度
dtHeight=rect.bottom-rect.top; //桌面高度
hwnd = CreateWindowEx(WS_EX_CLIENTEDGE,wc.lpszClassName,
"RFID读写标签功能实现",WS_VISIBLE|WS_OVERLAPPEDWINDOW,
(dtWidth-640)/2, /*窗体居中*/
(dtHeight-480)/2,
640,
480,
NULL,NULL,hInstance,NULL);
//MoveWindow(hwnd, (width-640)/2, (height-480)/2, 640, 480, FALSE);
if(hwnd == NULL) {
MessageBox(NULL, "Window Creation Failed!","Error!", MB_ICONEXCLAMATION|MB_OK);
return 0;
}
while(GetMessage(&msg, NULL, 0, 0) > 0) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
int i,w,j;
char readBuffer[1000];
char com[10];
char message1[100]="010C00030410002101060000";// write register
char message2[100]="010B000304140701000000";//selecet tag
char message3[100]="010B000304180320";//read one block [16]-[17]select block [18]-[21]=0000
char message4[100]="010F000304184221";//write one block [16]-[17]select block [18]-[25]content [26]-[29]=0000
DWORD dwBytesWrite=100;
COMSTAT ComStat;
DWORD dwErrorFlags;
TCHAR str[100];
DWORD nWantRead=100;
DWORD nReadRead;
FILE *fp;
DWORD errors;
int s;
HDC hdc;
static int cxChar, cyChar;
static HWND hwndButton0;
static HWND hwndButton1;
static HWND hwndButton2;
static HWND hwndEditbox0;
static HWND hwndEditbox1;
static HWND hwndEditbox2;
static HWND hwndEditbox3;
string strXy;
char x[5], y[5];
char order[10];
char buff[4096] = {0};
const int IDcmdButton1 = 1;
const int IDeditBox1 = 2;
const int IDcmdButton2 = 3;
const int IDeditBox2 = 4;
const int IDcmdButton0 = 5;
const int IDeditBox0 = 6;
cxChar = LOWORD(GetDialogBaseUnits());
cyChar = HIWORD(GetDialogBaseUnits());
HANDLE hCom;
switch (message) {
case WM_CREATE:
hwndButton0 = CreateWindow ( TEXT("button"), TEXT("打开串口"),
WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
cxChar * 18, cyChar * 0.5,
10 * cxChar, 2.5 * cyChar,
hwnd, (HMENU)IDcmdButton0, ((LPCREATESTRUCT) lParam)->hInstance, NULL);
if (!hwndButton0) MessageBox(NULL,"创建按钮失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndButton0,SW_SHOW);
UpdateWindow(hwndButton0);
hwndButton2 = CreateWindow ( TEXT("button"), TEXT("运行功能"),
WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
cxChar * 40, cyChar * 9.5,
30 * cxChar, 2.5 * cyChar,
hwnd, (HMENU)IDcmdButton2, ((LPCREATESTRUCT) lParam)->hInstance, NULL);
if (!hwndButton2) MessageBox(NULL,"创建按钮失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndButton2,SW_SHOW);
UpdateWindow(hwndButton2);
// 串口输入框
hwndEditbox0 = CreateWindow( TEXT("edit"),NULL,
WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE,
cxChar * 5, cyChar * 0.5,
10 * cxChar, 2.5 * cyChar,
hwnd,(HMENU)IDeditBox0,NULL,NULL);
if (!hwndEditbox0) MessageBox(NULL,"创建串口输入框失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndEditbox0,SW_SHOW);
UpdateWindow(hwndEditbox0);
// 功能选择输入框
hwndEditbox1 = CreateWindow( TEXT("edit"),NULL,
WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE,
cxChar * 5, cyChar * 5,
30 * cxChar, 3.5 * cyChar,
hwnd,(HMENU)IDeditBox1,NULL,NULL);
if (!hwndEditbox1) MessageBox(NULL,"创建功能选择输入框失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndEditbox1,SW_SHOW);
UpdateWindow(hwndEditbox1);
//指令补全框
hwndEditbox2 = CreateWindow( TEXT("edit"),NULL,
WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE,
cxChar * 40, cyChar * 5,
30 * cxChar, 3.5 * cyChar,
hwnd,(HMENU)IDeditBox2,NULL,NULL);
if (!hwndEditbox2) MessageBox(NULL,"创建指令补全框失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndEditbox2,SW_SHOW);
UpdateWindow(hwndEditbox2);
// 消息返回框
hwndEditbox3 = CreateWindow( TEXT("edit"),NULL,
WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE,
cxChar * 5, cyChar * 13,
65 * cxChar, 12 * cyChar,
hwnd,(HMENU)IDeditBox2,NULL,NULL);
if (!hwndEditbox3) MessageBox(NULL,"创建消息返回框失败","Message",MB_OK|MB_ICONERROR);
ShowWindow(hwndEditbox3,SW_SHOW);
UpdateWindow(hwndEditbox3);
return 0 ;
case WM_SIZE:
//GetWindowRect(hwnd, &rect);
//MoveWindow(hwndButton, (rect.right-rect.left)/2 - 15*cxChar ,\
//(rect.bottom-rect.top)/2 - 1.25*cxChar, 30*cxChar, 2.5*cyChar, FALSE);
return 0;
case WM_COMMAND:
//各控件的_click()事件
switch (LOWORD(wParam)) {
case 0:
PostQuitMessage(0);
break;
case IDcmdButton0:
GetWindowText(hwndEditbox0,com,5);
hCom=CreateFile(com,GENERIC_READ | GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL);
if(hCom == INVALID_HANDLE_VALUE)
{
MessageBox(NULL,"打开串口失败！！","Message",MB_OK|MB_ICONERROR);
return -1;
}
if(!SetupComm(hCom,1024,1024))
{
MessageBox(NULL,"设置缓冲区失败！！","Message",MB_OK|MB_ICONERROR);
return -1;
}
COMMTIMEOUTS TimeOuts;
TimeOuts.ReadIntervalTimeout=100;
TimeOuts.ReadTotalTimeoutMultiplier=100;
TimeOuts.ReadTotalTimeoutConstant=1000;
TimeOuts.WriteTotalTimeoutMultiplier=50;
TimeOuts.WriteTotalTimeoutConstant=2000;
SetCommTimeouts(hCom,&TimeOuts);
PurgeComm(hCom,PURGE_TXCLEAR|PURGE_RXCLEAR);
DCB dcb;
GetCommState(hCom, &dcb);
dcb.BaudRate = CBR_9600; //波特率
dcb.ByteSize = 8; // number of bits/byte, 4-8 指定端口当前使用的数据位
dcb.Parity = 0; // 0-4=no,odd,even,mark,space 指定端口当前使用的奇偶校验方法
dcb.StopBits = 1; //指定端口当前使用的停止位数
SetCommState(hCom,&dcb);
w=WriteFile(hCom,message1,strlen(message1),&dwBytesWrite,NULL);
if(!w)
{
MessageBox(NULL,"写串口失败1！！","Message",MB_OK|MB_ICONERROR);
return -1;
}
Sleep(100);
PurgeComm(hCom,PURGE_TXCLEAR);
ClearCommError(hCom,&dwErrorFlags,&ComStat);
//读缓冲区的数据
s=ReadFile(hCom,readBuffer,800,&nReadRead, NULL);
if(s==0)
{
MessageBox(NULL,"读取串口失败1！！","Message",MB_OK|MB_ICONERROR);
return -1;
}
MessageBox(NULL,"打开串口成功","Message",MB_OK);
break;
case IDeditBox1:
break;
case IDcmdButton2:
GetWindowText(hwndEditbox1,order,5);
if(order[0]=='s'){
SetWindowText(hwndEditbox3,"询卡");
try{
w=WriteFile(hCom,message2,strlen(message2),&dwBytesWrite,NULL);
}
catch(...){
fp=fopen("error.txt","w");
fprintf(fp,"exception");
fclose(fp);
}
if(!w)
{
MessageBox(NULL,"写串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
ClearCommError(hCom,&dwErrorFlags,&ComStat);
//读缓冲区的数据
s=ReadFile(hCom,readBuffer,800,&nReadRead, NULL);
if(s==0)
{
MessageBox(NULL,"读取串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
for(i=0;i<nReadRead;i++){
if(readBuffer[i]=='[' && readBuffer[i+1]!=',')
{
SetWindowText(hwndEditbox3,"RFID：");
SetWindowText(hwndEditbox3,readBuffer);
fp=fopen("RFID.txt","w");
for(j=i+1;readBuffer[j]!=',';j++)
{
fputc(readBuffer[j],fp);
}
fclose(fp);
putchar('\n');
break;
}
}
PurgeComm(hCom,PURGE_RXCLEAR);
}
else if(order[0]=='r'){
SetWindowText(hwndEditbox3,"读单块");
GetWindowText(hwndEditbox2,buff,7);
for(i=0;i<6;i++){
message3[16+i]=buff[i];
}
SetWindowText(hwndEditbox3,message3);
w=WriteFile(hCom,message3,strlen(message3),&dwBytesWrite,NULL);
if(!w)
{
MessageBox(NULL,"写串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
Sleep(1000);
PurgeComm(hCom,PURGE_TXCLEAR);
ClearCommError(hCom,&dwErrorFlags,&ComStat);
//读缓冲区的数据
s=ReadFile(hCom,readBuffer,800,&nReadRead, NULL);
PurgeComm(hCom,PURGE_RXCLEAR);
if(s==0)
{
MessageBox(NULL,"读取串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
for(i=0;i<nReadRead;i++)
if(readBuffer[i]=='[' && readBuffer[i+1]!=',')
{
SetWindowText(hwndEditbox3,"block:");
SetWindowText(hwndEditbox3,readBuffer);
fp=fopen("block.txt","w");
for(j=i+1;readBuffer[j]!=',';j++)
{
fputc(readBuffer[j],fp);
}
fclose(fp);
break;
}
}
else if(order[0]=='w'){
SetWindowText(hwndEditbox3,"写单块");
GetWindowText(hwndEditbox2,buff,15);
for(i=0;i<14;i++){
message4[16+i]=buff[i];
}
SetWindowText(hwndEditbox3,"指令补全完成");
w=WriteFile(hCom,message4,strlen(message4),&dwBytesWrite,NULL);
if(!w)
{
MessageBox(NULL,"写串口失败2","Message",MB_OK|MB_ICONERROR);
return -1;
}
Sleep(1000);
PurgeComm(hCom,PURGE_TXCLEAR);
ClearCommError(hCom,&dwErrorFlags,&ComStat);
SetWindowText(hwndEditbox3,"写串口成功");
}
break;
case IDeditBox2:
break;
}
return 0;
/*case WM_CLOSE:
if (IDYES==MessageBox(hwnd, "是否真的要退出？", "确认", MB_ICONQUESTION | MB_YESNO))
DestroyWindow(hwnd); //销毁窗口
return 0;*/
}
return DefWindowProc(hwnd, message, wParam, lParam);
}
你用try catch查看具体报错。