若是用過C#會發現String.Format是功能很是強大的字符串替換方法。c#
而在Js中,僅僅是提供了一個.replace方法。而且只能替換匹配到的第一字符串。須要進行大量的二次包裝或則循環使用。數組
固然也能夠經過正則來進行。可是又至關的麻煩以及代碼的可讀性不好。app
爲何咱們不能經過對String的擴展來提供相似c#的String.Format的功能呢?ide
老規矩,核心代碼奉上。this
String.prototype.Format = function () { var returnValue = this; for (var i = 0; i < arguments.length; i++) { var arg = arguments[i]; var key = ""; var value = ""; //參數若是爲string 則使用傳統的查找{i}進行替換 if (typeof arg == "string") { key = i; value = arg; } else if (arg instanceof Array) { //若是參數爲數組則轉爲傳統的Format調用方式進行二次調用 returnValue = returnValue.Format.apply(returnValue, arg); continue; } else { //若是參數爲對象,則按照KeyValue數據格式進行替換 key = arg.key; value = arg.value; } //設置須要轉譯的保留符號 var keySymple = [ { reg: /\\/ig, value: "\\\\" }, { reg: /\{/ig, value: "\\{" }, { reg: /\}/ig, value: "\\}" }, { reg: /\)/ig, value: "\\)" }, { reg: /\(/ig, value: "\\(" }, ] //查找保留符號進行轉譯 for (var j = 0; j < keySymple.length; j++) { var sympleReplace = keySymple[j]; key = key.toString().replace(sympleReplace.reg, sympleReplace.value); } var reg = new RegExp("\\{" + key + "\\}", "ig"); returnValue = returnValue.replace(reg, value); } return returnValue; }
而後接着就是使用代碼了prototype
var demoStr="this is a {0} {1}" demoStr.Format("hot","day")//return "this is a hot day" demoStr.Format(["hot","day"])//return "this is a hot day" var demoStr="my name is {Name},age {Age}" demoStr.Format({key:"Name",value:"Happy"},{key:"Age",value:"20"}) //return "my name is Happy,age 20" demoStr.Format([{key:"Name",value:"Happy"},{key:"Age",value:"20"}]) //return "my name is Happy,age 20"
參數支持params和array兩種結構orm
同時支持string以及{key:,value:,}兩種數據對象