1. 字符串替换

function stringFormate(string) {
    var params = [].slice.call(arguments,1);
    console.log(params);
    var regex = /\{(\d+)\}/g;
    var str = string.replace(regex,function(){
        index = arguments[1];
        return params[index];
    });
    return str;
};

2. 简单的模板引擎

var tmplateEngine = function(tpl,data){
    var regex = /<%([^%>]+)?%>/g;
    while (match = regex.exec(tpl)) {
        tpl = tpl.replace(match[0],data[match[1]]); 
    };
    return tpl;
};
var tpl = '<p>Hello,my name is <%name%>.I\'m <%age%> years old.</p>'
var data = {
    name: 'michael',
    age: 27
}
var string = tmplateEngine(tpl,data);
console.log(string);  //<p>Hello,my name is michael.I'm 27 years old.</p>