一个简单的js模板引擎

自己写来快速生成html代码用的, 因为要求比较简单，也就没用网上的模板解析引擎了

//charset gbk

/* 快速模板处理
 * author: gaohuia 2013.06.05
 */

function Render(html, config) {
	/* 模板 */
	this.html = html;

	/* 对默认值进行覆盖 */
	if (config) {
		for (var key in config) {
			this.config[key] = config[key];
		}
	}
}
Render.prototype = {
	/* 配置 */
	config: {
		allowEmpty: false /*设置值是否为空字符*/
	},

	html: "',
	htmlCollection: [],
	varCollection: [],
	onRenderTag: function(tag, rowData) {},
	/*
	 * 渲染所有数据，data被视为一个行数据的集合，如果data是一个对象，则自动作为一个行对象来渲染
	 */
	renderData: function(data) {
		/*
		 * 分析html文本, 提取变量
		 */
		this.prepareHtml();

		if (data instanceof Array) {
			var htmls = [];
			for (var i = 0; i < data.length; i++) {
				htmls.push(this.fetchRow(data[i]));
			}
			return htmls.join('');
		} else if (data instanceof Object) {
			return this.fetchRow(data);
		} else {
			throw "data必需是一个Object或Array的一个实例";
		}
	},
	/*
	 * 将一行视为一个模板渲染的对象
	 */
	fetchRow: function(rowData) {
		var htmlCollection = this.htmlCollection;
		var varCollection = this.varCollection;

		/**/

		var htmls = [];
		for (var i = 0; i < varCollection.length; i++) {
			var varTag = varCollection[i];

			/*
			 * 变量在字典中存在的情况
			 */

			if (rowData.hasOwnProperty(varTag.varName) && rowData[varTag.varName] != null && (rowData[varTag.varName] != '' || this.config['allowEmpty'])) {
				varTag.varValue = rowData[varTag.varName];
				this.onRenderTag(varTag, rowData);
			} else {
				if (varTag.varAttr.hasOwnProperty('default')) {
					varTag.varValue = varTag.varAttr['default'];
				} else {
					varTag.varValue = '';
				}
			}

			htmls.push(htmlCollection[i]);
			htmls.push(varTag.varValue);
		}

		htmls.push(htmlCollection[i]);
		return htmls.join('');
	},
	prepareHtml: function() {
		var html = this.html;
		if (html.length == 0) return;
		var exp = /\{\$(.*?)\}/g;
		var varCollection = [];
		var htmlCollection = [];

		var arr = null;
		var lastIndex = 0;
		while ((arr = exp.exec(html)) != null) {
			var varAttr = {};
			var varFull = arr[1];
			var tagFull = arr[0];

			/*
			 * 对多于空格进替换，方便后面提取标签属性
			 */
			varFull = varFull.replace(/\s+/g, " ");

			var tmp = varFull.split(' ');
			var varName = tmp[0];
			for (var i = 1; i < tmp.length; i++) {
				var attrPair = tmp[i].split('=');
				var attrName = attrPair[0];
				var attrValue = attrPair[1].replace(/[\"\']/g, "");
				varAttr[attrName] = attrValue;
			}

			/*
			 * 一个单独的标签, 用户可以根据标签的属性对标签的值做不同的处理
			 */
			var varSingle = {
				tagFull: tagFull,
				varName: varName,
				varFull: varFull,
				varValue: '',
				varAttr: varAttr
			}

			/* 为变量设置默认值 */
			if (varSingle.varAttr.hasOwnProperty('default')) {
				varSingle.varValue = varSingle.varAttr['default'];
			}

			varCollection.push(varSingle);
			var htmlPiece = html.substr(lastIndex, arr.index - lastIndex);
			htmlCollection.push(htmlPiece);

			/*
			 * 准备下一次标签寻找
			 */
			lastIndex = arr.index + arr[0].length;
		}

		htmlPiece = html.substr(lastIndex);
		htmlCollection.push(htmlPiece);

		this.htmlCollection = htmlCollection;
		this.varCollection = varCollection;
	}
}