jQuery extend扩展String原型

jQuery.extend(String.prototype, {
    isPositiveInteger:function(){
        return (new RegExp(/^[1-9]\d*$/).test(this));
    },
    isInteger:function(){
        return (new RegExp(/^\d+$/).test(this));
    },
    isNumber: function(value, element) {
        return (new RegExp(/^-?(?:\d+|\d{1,3}(?:,\d{3})+)(?:\.\d+)?$/).test(this));
    },
    
    trim:function(){
        return this.replace(/(^\s*)|(\s*$)|\r|\n/g, "");
    },
    trans:function() {
        return this.replace(/</g, '<').replace(/>/g,'>').replace(/"/g, '"');
    },
    replaceAll:function(os, ns) {
        return this.replace(new RegExp(os,"gm"),ns);
    },
    skipChar:function(ch) {
        if (!this || this.length===0) {return '';}
        if (this.charAt(0)===ch) {return this.substring(1).skipChar(ch);}
        return this;
    },

    /**
     * check if Valid password
     */
    isValidPwd:function() {
        return (new RegExp(/^([_]|[a-zA-Z0-9]){6,32}$/).test(this)); 
    },
    /**
     * check if Valid email
     */
    isValidMail:function(){
        return(new RegExp(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/).test(this.trim()));
    },
    
    isSpaces:function() {
        for(var i=0; i<this.length; i+=1) {
            var ch = this.charAt(i);
            if (ch!=' '&& ch!="\n" && ch!="\t" && ch!="\r") {return false;}
        }
        return true;
    },
    isPhone:function() {
        return (new RegExp(/(^([0-9]{3,4}[-])?\d{3,8}(-\d{1,6})?$)|(^\([0-9]{3,4}\)\d{3,8}(\(\d{1,6}\))?$)|(^\d{3,8}$)/).test(this));
    },
    isURL:function(){
        return (new RegExp(/^[a-zA-z]+:\/\/(\w+(-\w+)*)(\.(\w+(-\w+)*))*(\?\S*)?$/).test(this)); 
    }
});