Question

VC中如果知道电脑上有几个串口可用？

如题，请给出代码~！
在线等.

Answer 1

//枚举串口
//参数：bEnablePort，哪个串口有效，bEnablePort[0]表示COM1，bEnablePort[n-1]表示COMn
//返回值：有效的串口个数
int EnumAllComPort(bool* bEnablePort)
{
int nCommSum = 0;//串口个数

HANDLE hCom;
CString str;

for(int i=1;i<=256;i++)
{
str.Format(_T("COM%d"),i);
hCom = CreateFile(str, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);

if (hCom == INVALID_HANDLE_VALUE)
{
bEnablePort[i-1] = false;
continue;
}
else
{
bEnablePort[i-1] = true;
}

CloseHandle(hCom);
nCommSum++;
}

return nCommSum;
}

Answer 2

1、一般PC电脑本身就自带1个，需要多个的话需要用扩展卡。
2、程序：
//枚举串口
//参数：bEnablePort，哪个串口有效，bEnablePort[0]表示COM1，bEnablePort[n-1]表示COMn
//返回值：有效的串口个数
int EnumAllComPort(bool* bEnablePort)
{
int nCommSum = 0;//串口个数

HANDLE hCom;
CString str;

for(int i=1;i<=256;i++)
{
str.Format(_T("COM%d"),i);
hCom = CreateFile(str, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);

if (hCom == INVALID_HANDLE_VALUE)
{
bEnablePort[i-1] = false;
continue;
}
else
{
bEnablePort[i-1] = true;
}

CloseHandle(hCom);
nCommSum++;
}

return nCommSum;
}

Answer 3

HKEY hKey;
int rtn;
rtn = RegOpenKeyEx( HKEY_LOCAL_MACHINE, "Hardware\\DeviceMap\\SerialComm",
NULL, KEY_READ, &hKey);
if( rtn == ERROR_SUCCESS) // 打开串口注册表
{
int i=0;
char portName[256],commName[256];
DWORD dwLong,dwSize;
while(1)
{
dwSize = sizeof(portName);
dwLong = dwSize;
rtn = RegEnumValue( hKey, i, portName, &dwLong,
NULL, NULL, (PUCHAR)commName, &dwSize );
if( rtn == ERROR_NO_MORE_ITEMS ) // 枚举串口
break;
i++;
}
RegCloseKey(hKey);
}