js常用自定义公共函数汇总

String.prototype.trim = function(){ 
return this.replace(/(^\s*)|(\s*$)/g, ""); 
} //检查是否是日期格式 
function isDate(datestr){ 
var result = datestr.match(/((^((1[8-9]\d{2})|([2-9]\d{3}))(-)(10|12|0?[13578])(-)(3[01]|[12][0-9]|0?[1-9])$)|(^((1[8-9]\d{2})|([2-9]\d{3}))(-)(11|0?[469])(-)(30|[12][0-9]|0?[1-9])$)|(^((1[8-9]\d{2})|([2-9]\d{3}))(-)(0?2)(-)(2[0-8]|1[0-9]|0?[1-9])$)|(^([2468][048]00)(-)(0?2)(-)(29)$)|(^([3579][26]00)(-)(0?2)(-)(29)$)|(^([1][89][0][48])(-)(0?2)(-)(29)$)|(^([2-9][0-9][0][48])(-)(0?2)(-)(29)$)|(^([1][89][2468][048])(-)(0?2)(-)(29)$)|(^([2-9][0-9][2468][048])(-)(0?2)(-)(29)$)|(^([1][89][13579][26])(-)(0?2)(-)(29)$)|(^([2-9][0-9][13579][26])(-)(0?2)(-)(29)$))/); 
if(result==null){ 
return "no"; 
} 
return "yes"; 
} 
//此方法以上面效果一致 
function isDate2(datestr) { 
var result = datestr.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})$/); 
if (result == null) 
return "no"; 
var d = new Date(result[1], result[3] - 1, result[4]); 
if((d.getFullYear() == result[1] && (d.getMonth() + 1) == result[3] && d.getDate() == result[4])){ 
return "yes"; 
} 
return "no"; 
} 
//判断输入的字符是否为中文 
function IsChinese(str){ 
if(str.length!=0){ 
reg=/^[\u0391-\uFFE5]+$/; 
if(!reg.test(str)){ 
// alert("对不起，您输入的字符串类型格式不正确!"); 
return "no"; 
} 
} 
return "yes"; 
} 

//判断是否为空 
function isEmpty(str){ 
if(str==null||typeof str=="undefined"||str.trim()==""){ 
return true; 
}else{ 
return false; 
} 
} 
//固定电话 
function testTelephone(phone){ 
var phone_reg = new RegExp(/^([+]{0,1}\d{3,4}|\d{3,4}-)?\d{7,8}$/); 
if(!phone_reg.test(phone)){ 
return "no"; 
} 
return "yes"; 
} 
//折扣 
function isDiscount(discount){ 
var phone_reg = new RegExp(/^(0([\.]\d{1,2})|1|1.00|1.0)$/); 
if(!phone_reg.test(discount)){ 
return "no"; 
} 
return "yes"; 
} 
//手机号码 
function testMobile(mobile){ 
var mobile_reg = new RegExp(/^0{0,1}1[0-9]{10}$/); 
if(!mobile_reg.test(mobile)){ 
return "no"; 
} 
return "yes"; 
} 
//QQ号码从10000开始 
function testQQ(qq){ 
var qq_reg = new RegExp(/^[1-9][0-9]{4,}$/); 
if(!qq_reg.test(qq)){ 
return "no"; 
} 
return "yes"; 
} 
//电子邮件 
function testEmail(email){ 
var email_reg = new RegExp(/^\w+([-+.]\w+)*@\w+([-.]\w+)*.\w+([-.]\w+)*$/); 
if(!email_reg.test(email)){ 
return "no"; 
} 
return "yes"; 
} 
//不带符号的正整数 
function testPlusDigit(digit){ 
var plusDigit_reg = new RegExp(/^\d+$/); 
if(!plusDigit_reg.test(digit)){ 
return "no"; 
} 
return "yes"; 
} 
//DOUBLE价格 
function testPriceFormat(str){ 
var priceFormatReg = new RegExp(/^\d+(.\d{1,2})?$/); 
if(!priceFormatReg.test(str)){ 
return "no"; 
} 
return "yes"; 
} 
//身份证 
function testIDCard(str){ 
var IDCardReg = new RegExp(/(^\d{15}$)|(^\d{17}([0-9]|X)$)/); 
if(!IDCardReg.test(str)){ 
return "no"; 
} 
return "yes"; 
} 
//2012-06-19日期格式 
function testDate(str){ 
var dateReg = new RegExp(/(^\d{4}-[0,1][0-9]-[0-3][0-9]$)/); 
if(!dateReg.test(str)){ 
return "no"; 
} 
return "yes"; 
} 

//浮点数精确运算(加法) 
function accAdd(arg1,arg2){ 
var r1,r2,m,n; 
try{r1=arg1.toString().split(".")[1].length}catch(e){r1=0} 
try{r2=arg2.toString().split(".")[1].length}catch(e){r2=0} 
m=Math.pow(10,Math.max(r1,r2)); 
n=(r1>=r2)?r1:r2; 
return ((arg1*m+arg2*m)/m).toFixed(n); 
} 
Number.prototype.add = function (arg){ 
return accAdd(arg,this); 
} 
//浮点数精确运算(减法) 
function accSub(arg1,arg2){ 
return accAdd(arg1,-arg2); 
} 
Number.prototype.subtract = function (arg){ 
return accSub(this,arg); 
} 
//浮点数精确运算(乘法) 
function accMul(arg1,arg2) 
{ 
var m=0,s1=arg1.toString(),s2=arg2.toString(); 
try{m+=s1.split(".")[1].length}catch(e){} 
try{m+=s2.split(".")[1].length}catch(e){} 
return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m) 
} 
Number.prototype.mul = function (arg){ 
return accMul(arg, this); 
} 
//浮点数精确运算(除法) 
function accDiv(arg1,arg2){ 
var t1=0,t2=0,r1,r2; 
try{t1=arg1.toString().split(".")[1].length}catch(e){} 
try{t2=arg2.toString().split(".")[1].length}catch(e){} 
with(Math){ 
r1=Number(arg1.toString().replace(".","")) 
r2=Number(arg2.toString().replace(".","")) 
return (r1/r2)*pow(10,t2-t1); 
} 
} 
Number.prototype.div = function (arg){ 
return accDiv(this, arg); 
} 
//限制输入数字 
function isNumber(e) { 
if ($.browser.msie) { 
if ( ((event.keyCode > 47) && (event.keyCode < 58)) || 
(event.keyCode == 8) ) { 
return true; 
} else { 
return false; 
} 
} else { 
if ( ((e.which > 47) && (e.which < 58)) || 
(e.which == 8) ) { 
return true; 
} else { 
return false; 
} 
} 
} 

//字符串长度截取 
function cutstr(str, len) { 
var temp; 
var icount = 0; 
var patrn = /[^\x00-\xff]/; 
var strre = ""; 
for (var i = 0; i < str.length; i++) { 
if (icount < len - 1) { 
temp = str.substr(i, 1); 
if (patrn.exec(temp) == null) { 
icount = icount + 1; 
} else { 
icount = icount + 2; 
} 
strre += temp; 
} else { 
break 
} 
} 
return strre + "..."; 
} 
//获取域名主机 
function getHost(url) { 
var host = "null"; 
if (typeof url == "undefined" || null == url) { 
url = window.location.href; 
} 
var regex = /^\w+\:\/\/([^\/]*).*/; 
var match = url.match(regex); 
if (typeof match != "undefined" && null != match) { 
host = match[1]; 
} 
return host; 
} 
//判断某个值是否在所在范围 
//rang=1 表示正整数[0,2147483647] 2表示float[0,3.4028235E38] 
//return= 'empty' 表示输入为空, 
function isRang(str,rang){ 
if(typeof str == "number"){ 
var num = Number(str); 
//判断是否在正整数范围 
if( rang == 1){ 
if(testPlusDigit(num)=="yes"){ 
if(num>=0&&num<=2147483647){ 
return "is_int"; 
}else{ 
return "is_not_int_rang"; 
} 
}else{ 
return "is_not_int"; 
} 
}else if(rang == 2){ 
if(testPriceFormat(num)=="yes"){ 
if(num>=0&&num<=3.4028235E38){ 
return "is_float"; 
}else{ 
return "is_not_float_rang"; 
} 
}else{ 
return "is_not_float"; 
} 
}else{ 
return "rang_is_not_right"; 
} 
}else{ 
return "is_not_number"; 
} 
}