var letterChineseReg = /^[^"']{1,48}$/;function validateName(name, len) {    if (len==48) {        if (!letterChineseReg.exec(name)) {            return false;        }    }    strLen = name.replace(/[^\x00-\xff]/g, "***").length;  // non letter is the lenght of three chars    if (strLen>len) {        return false;    }    return true;}if (!validateName(rep_name, 48)) {    showWarningMsg("名稱不合法");    return false;}這段正則是做什么判斷var letterChineseReg = /^[^"']{1,48}$/name.replace(/[^\x00-\xff]/g, "***").length