function checkstr(str)
{//获取中英文字符串长度
var sTargetStr=document.getElementById(str).value;
var sTmpStr, sTmpChar;
var nOriginLen = 0;
var nStrLength = 0;
sTmpStr = new String(sTargetStr);
nOriginLen = sTmpStr.length;
for ( var i=0 ; i < nOriginLen ; i++ )
{
sTmpChar = sTmpStr.charAt(i);
if (escape(sTmpChar).length > 4)
{
nStrLength += 2;
} else if (sTmpChar!='\r')
{
nStrLength ++;
}
}