javascript小技巧[8]

//检验连接是否有效
function getXML(URL) 
{
 var xmlhttp = new ActiveXObject("microsoft.xmlhttp");
 xmlhttp.Open("GET",URL, false); 
 try
 { 
  xmlhttp.Send();
 }
 catch(e){}
 finally 
 {
  var result = xmlhttp.responseText;
  if(result) 
  {
   if(xmlhttp.Status==200)
   {
    return(true);
   }
   else 
   {
    return(false);
   }
  }
  else 
  {
   return(false);
  }
 }
}
//POST代替FORM
<SCRIPT language="VBScript">
Function URLEncoding(vstrIn)
    strReturn = ""
    For i = 1 To Len(vstrIn)
        ThisChr = Mid(vStrIn,i,1)
        If Abs(Asc(ThisChr)) < &HFF Then
            strReturn = strReturn & ThisChr
        Else
            innerCode = Asc(ThisChr)
            If innerCode < 0 Then
                innerCode = innerCode + &H10000
            End If
            Hight8 = (innerCode  And &HFF00)\ &HFF
            Low8 = innerCode And &HFF
            strReturn = strReturn & "%" & Hex(Hight8) &  "%" & Hex(Low8)
        End If
    Next
    URLEncoding = strReturn
End Function
Function bytes2BSTR(vIn)
    strReturn = ""
    For i = 1 To LenB(vIn)
        ThisCharCode = AscB(MidB(vIn,i,1))
        If ThisCharCode < &H80 Then
            strReturn = strReturn & Chr(ThisCharCode)
        Else
            NextCharCode = AscB(MidB(vIn,i+1,1))
            strReturn = strReturn & Chr(CLng(ThisCharCode) * &H100 +
CInt(NextCharCode))
            i = i + 1
        End If
    Next
    bytes2BSTR = strReturn
End Function
dim strA,oReq
strA = URLEncoding("submit1=Submit&text1=中文")
set oReq = CreateObject("MSXML2.XMLHTTP")
oReq.open "POST","http://ServerName/VDir/TstResult.asp",false
oReq.setRequestHeader "Content-Length",Len(strA)
oReq.setRequestHeader "CONTENT-TYPE","application/x-www-form-urlencoded"
oReq.send strA
msgbox bytes2BSTR(oReq.responseBody)
</SCRIPT>
//readyState是xmlhttp返回数据的进度，0=载入中,1=未初始化,2=已载入,3=运行中,4=完成
//组件是否安装
isComponentInstalled("{6B053A4B-A7EC-4D3D-4567-B8FF8A1A5739}", "componentID"))
//检查网页是否存在

function CheckURL(URL)
{
  var xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  xmlhttp.Open("GET",URL, false);
  try
  { 
    xmlhttp.Send(); 
    var result = xmlhttp.status;
  }
  catch(e) {return(false); }
  if(result==200)
  { 
    return true;
  }
  xmlhttp = null;
  return false;
}
//连接数据库