StringBuilder效果

//对象定义（构造函数) //参数：所有参数须为字符串形式. //当参数长度为1时，参数值将是字符串之间连接的分隔符 //当参数长度大于1时，最后一位将是字符串之间的分隔符,其余的参数将是字符串值 //当不指定参数时，分隔符默认为空白 //也可以不指定分隔符，而在ToString中显式指定分隔符 //如：var str = new StringBuilder(',')； 则在ToString时，将使用,号作为分隔符连接字符串 // var str = new StringBuilder('a','b','c',','); 则在ToString时，将输出 'a,b,c' function StringBuilder() {     this._buffers = [];     this._length = 0;     this._splitChar = arguments.length > 0 ? arguments[arguments.length - 1] : '';

    if (arguments.length > 0) {         for (var i = 0, iLen = arguments.length - 1; i < iLen; i++) {             this.Append(arguments[i]);         }     } } //向对象中添加字符串 //参数：一个字符串值 StringBuilder.prototype.Append = function (str) {     this._length += str.length;     this._buffers[this._buffers.length] = str; } StringBuilder.prototype.Add = StringBuilder.prototype.append; //向对象附加格式化的字符串 //参数：参数一是预格式化的字符串，如：'{0} {1} {2}' //格式参数可以是数组，或对应长度的arguments, //参见示例 StringBuilder.prototype.AppendFormat = function () {     if (arguments.length > 1) {         var TString = arguments[0];         if (arguments[1] instanceof Array) {             for (var i = 0, iLen = arguments[1].length; i < iLen; i++) {                 var jIndex = i;                 var re = eval("/\\{" + jIndex + "\\}/g;");                 TString = TString.replace(re, arguments[1][i]);             }         }         else {             for (var i = 1, iLen = arguments.length; i < iLen; i++) {                 var jIndex = i - 1;                 var re = eval("/\\{" + jIndex + "\\}/g;");                 TString = TString.replace(re, arguments[i]);             }         }         this.Append(TString);     }     else if (arguments.length == 1) {         this.Append(arguments[0]);     } } //字符串长度（相当于ToString()后输出的字符串长度 StringBuilder.prototype.Length = function () {     if (this._splitChar.length > 0 && (!this.IsEmpty())) {         return this._length + (this._splitChar.length * (this._buffers.length - 1));     }     else {         return this._length;     } } //字符串是否为空 StringBuilder.prototype.IsEmpty = function () {     return this._buffers.length <= 0; } //清空 StringBuilder.prototype.Clear = function () {     this._buffers = [];     this._length = 0; } //输出 //参数：可以指定一个字符串（或单个字符），作为字符串拼接的分隔符 StringBuilder.prototype.ToString = function () {     if (arguments.length == 1) {         return this._buffers.join(arguments[1]);     }     else {         return this._buffers.join(this._splitChar);     } }