js 验证字符串功能实例代码如下所示：
//去除空格
function jsTrim(value) {
var reg = /^\S$/;
if (!value) return "";
if (value.length == 0)
return value;
else {
var lp, rp;
lp = 0; rp = value.length - 1;
while ((value.charAt(lp) == " " || (value.charCodeAt(lp) < 128 ? (reg.test(value.charAt(lp)) == false ? true : false) : false) || value.charAt(rp) == " " || (value.charCodeAt(rp) < 128 ? (reg.test(value.charAt(rp)) == false ? true : false) : false)) && rp >= lp) {
if (value.charAt(lp) == " " || value.charCodeAt(lp) < 128 ? (reg.test(value.charAt(lp)) == false ? true : false) : false)
lp++;
if (value.charAt(rp) == " " || value.charCodeAt(rp) < 128 ? (reg.test(value.charAt(rp)) == false ? true : false) : false)
rp--;
}
if (lp > rp)
return "";
else
return (value.substring(lp, rp + 1));
}
}
//字符串长度
function strlength(s) {
var s_length = s.length;
return s_length;
}
//手机号码验证函数
String.prototype.Trim = function() {
var m = this.match(/^\s*(\S+(\s+\S+)*)\s*$/);
return (m == null) ? "" : m[1];
}
String.prototype.isMobile = function() {
return (/^(?:13\d|15\d|18\d|19\d|17\d|14\d)-?\d{5}(\d{3}|\*{3})$/.test(this.Trim()));
}
//*判别电话号码，手机号是否有效
//*返回 true:false
//*/
function checkPhone(phone)
{
//验证电话号码手机号码，包含153，159号段
if (phone==""){
alert("电话号码不能为空！");
return false;
}
if (phone != ""){
var p1 = /^(([0\+]\d{2,3}-)?(0\d{2,3})-)?(\d{7,8})(-(\d{3,}))?$/;
var me = false;
if (p1.test(phone)) me=true;
if (!me){
//alert('对不起，您输入的电话号码有错误。区号和电话号码之间请用-分割');
return false;
}
}
return true;
}
//邮箱地址验证函数
function checkmail(mail) {
// var strr;
// re = /(\w+@\w+\.\w+)(\.{0,1}\w*)(\.{0,1}\w*)/i;
// re.exec(mail);
// if (RegExp.$3 != "" && RegExp.$3 != "." && RegExp.$2 != ".")
// strr = RegExp.$1 + RegExp.$2 + RegExp.$3
// else {
// if (RegExp.$2 != "" && RegExp.$2 != ".")
// strr = RegExp.$1 + RegExp.$2
// else
// strr = RegExp.$1
// }
// if (strr != mail) { return false } else { return true }
// return true;
var remail = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
return mail.match(remail);
}
//判断数字
function CheckNumber(n) {
var checkOK = "0123456789-.";
var allValid = true;
var decPoints = 0;
var allNum = "";
for (i = 0; i < n.length; i++) {
ch = n.charAt(i);
for (j = 0; j < checkOK.length; j++)
if (ch == checkOK.charAt(j))
break;
if (j == checkOK.length) {
allValid = false;
break;
}
if (ch == ".") {
allNum += ".";
decPoints++;
}
else
allNum += ch;
}
if (!allValid)
return false;
if (decPoints > 1)
return false;
return true;
}
//判断数字
function CheckN(n) {
var checkOK = "0123456789";
var allValid = true;
var decPoints = 0;
var allNum = "";
for (i = 0; i < n.length; i++) {
ch = n.charAt(i);
for (j = 0; j < checkOK.length; j++)
if (ch == checkOK.charAt(j))
break;
if (j == checkOK.length) {
allValid = false;
break;
}
if (ch == ".") {
allNum += ".";
decPoints++;
}
else
allNum += ch;
}
if (!allValid)
return false;
if (decPoints > 1)
return false;
return true;
}
var g_MINY = 1601;
var g_MAXY = 4500;
var rgMC = new Array(12);
rgMC[0] = 31; rgMC[1] = 28; rgMC[2] = 31; rgMC[3] = 30; rgMC[4] = 31; rgMC[5] = 30; rgMC[6] = 31; rgMC[7] = 31; rgMC[8] = 30; rgMC[9] = 31; rgMC[10] = 30; rgMC[11] = 31;
function isdigit(c) {
return (c >= '0' && c <= '9');
}
function GetMonthCount(m, y) {
var c = rgMC[m - 1];
if ((2 == m) && IsLeapYear(y)) c++;
return c;
}
function atoi(s) {
var t = 0;
for (var i = 0; i < s.length; i++) {
var c = s.charAt(i);
if (!isdigit(c)) return t;
else t = t * 10 + (c - '0');
}
return t;
}
//判断日期
function CheckDate(t) {
var l = t.length;
if (0 == l) return false;
var cSp = '\0';
var sSp1 = '';
var sSp2 = '';
for (var i = 0; i < t.length; i++) {
var c = t.charAt(i);
if (c == ' ' || isdigit(c)) continue;
else if (cSp == '\0' && (c == '/' || c == '-' || c == '.')) {
cSp = c;
sSp1 = t.substring(i + 1, l);
}
else if (c == cSp) sSp2 = t.substring(i + 1, l);
else if (c != cSp) return false;
}
if (0 == sSp1.length) return false;
var m;
var d;
var y;
if (0 == sSp2.length) return false;
m = atoi(sSp1);
d = atoi(sSp2);
y = atoi(t);
if (y < 100) {
y = 1900 + y;
while (y < g_yLow) y = y + 100;
}
if (y < g_MINY || y > g_MAXY || m < 1 || m > 12) return false;
if (d < 1 || d > GetMonthCount(m, y)) return false;
g_month = m;
g_day = d;
g_year = y;
return true;
}
//验证字符串必须为数字字母组合
function isNumAndStr(elem){
var str = elem.value;
var regexpUperStr=/[A-Z]+/;
var reexpLowerStr=/[a-z]+/;
var regexpNum=/\d+/;
var uperStrFlag = regexpUperStr.test(str);
var lowerStrFlag = reexpLowerStr.test(str);
var numFlag = regexpNum.test(str);
if((uperStrFlag&&lowerStrFlag)||(lowerStrFlag&&numFlag)||(uperStrFlag&&numFlag))
return true;
else
return false;
}
//验证字符串必须为数字跟字母的组合
function checkPSW(str) {
if (str != "") {
var p1 = /(?!^[0-9]*$)(?!^[a-zA-Z]*$)^([a-zA-Z0-9]{2,})$/;
var me = false;
if (p1.test(str)) me = true;
if (!me) {
return false;
}
}
return true;
}
//验证字符串必须为数字跟字母的组合
function checklen(str) {
if (str.length < 8 ) {
return false;
}
return true;
}
//单价
function ISprice(v) {
var Mreg = /^[0-9]{1,10}(\.[0-9]{1,3})?$/;
if (Mreg.test(v)) {
return true;
}
else {
return false;
}
} 以上所述是小编给大家介绍的JS验证字符串功能，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持！