//截取字符串包含中文处理 
//(串,长度,增加...) 
function subString(str, len, hasDot) 
{ 
    var newLength = 0; 
    var newStr = ""; 
    var chineseRegex = /[^\x00-\xff]/g; 
    var singleChar = ""; 
    var strLength = str.replace(chineseRegex,"**").length; 
    for(var i = 0;i < strLength;i++) 
    { 
        singleChar = str.charAt(i).toString(); 
        if(singleChar.match( chineseRegex ) != null) 
        { 
            newLength += 2; 
        }     
        else 
        { 
            newLength ++; 
        } 
        if(newLength > len) 
        { 
            break; 
        } 
        newStr += singleChar; 
    } 
     
    if(hasDot && strLength > len) 
    { 
        newStr += "..."; 
    } 
    document.write( newStr ); 
}

function strbytelen(str)
{
	var i;
	var len;
	len = 0;
	for (i=0;i<str.length;i++)
	{
		if (str.charCodeAt(i)>255) len+=2; else len++;
	}
	return len;
}