写了一个打印信息的函数比Alert强大，类似Firebug中的console.table

有时候，特别是在Ajax请求返回数据时我们需要知道返回数据的结构，如果是Object，使用Alert是打印不出来的，使用Firebug中的 console 可以查看，我自己写了一个函数，有点像这个，有时候觉得使用console还不够直观，所以自己想办法写一个，不过现在支持的层级就三层，多了就不行了，多了就出现object。

 

if(!window.debug){
	window.debug = {};//选择一个自己的命名，千万别跟别人的冲突
};
debug.info = function(obj){
	if (typeof _deBugStatus_ !== "undefined") {
		return;
	};
	var version = "1.0",str = "",type,oLen = 0,ml=0,subStr = "",oimStr = "",aArr = "";

	var st=document.createElement("style");
	st.innerHTML = '' +
				   '.layer{font-family:Arial; font-size:14px; color:#333; line-height:150%; width:100%; height:100%; background:rgba(0,0,0,0.5); position:absolute; left:0; top:0; z-index:9999}' +
				   '.debug-box{width:900px; position:relative; left:50%; top:50%; margin-left:-450px; margin-top:-250px; background:white; box-shadow:0 0 50px rgba(0,0,0,0.5);}' +
				   '.debug-title{line-height:35px; padding: 0 10px; border-bottom:1px solid #AE0; background:#DED}' +
				   '.debug-names{width:20%; float:left; display:inline-block; *display:inline; *zoom:1; color:green; text-indent:5px}' +
				   '.debug-values{width:70%; float:right; color:orange}' +
				   '.debug-close{line-height:35px; position:absolute; right:0; top:0; color:#666; padding:0 10px; cursor:pointer}' +
				   '.uls{padding:0; margin:30px}' +
				   '.debug-clear{clear:both; line-height:0; height:0;}' +
				   '.debug-line{width:5%; float:left; color:blue}' +
				   '.debug-cs{overflow-y:auto; height:500px; padding-bottom:10px}' +
				   '#debugLayer li{border-bottom:1px solid #EEE;list-style:none; line-height:30px;}' +
				   '#debugLayer li:hover{background:#EDF4ED}' +
				   '.debug-obj-info{color:#666;}' +
				   '.debug-obj{font-weight:bold; color:green; margin:10px}';



	var h = document.getElementsByTagName("head")[0];
	h.appendChild(st);

	if (typeof obj === "string") {
		str = obj;
		type = "String";
	} else if (typeof obj === "object") {
		if (obj instanceof Array) {
			for (var i = 0, len = obj.length; i < len; i++) {
				str += '<li><div class="debug-names">'+ i +'</div><div class="debug-line">=></div><div class="debug-values">' + obj[i] + '</div><div class="debug-clear"></div></li>';
			}
			type = "Array";
			oLen = len;
		} else {
			for (var i in obj) {
				if (typeof obj[i] == "object") {
					if (obj[i]instanceof Array) {
						for (var m = 0; m < obj[i].length; m++) {
							if (typeof obj[i] == "object") {
								if (obj[i]instanceof Array) {
									var _a = "";
									for (var k = 0; k < obj[i].length; k++) {
										_a += '<div class="debug-names">' + k + '</div><div class="debug-line">=></div><div class="debug-values">' + obj[i][k] + '</div><div class="debug-clear"></div>';
									}
									aArr += '<div class="debug-names">' + m + '</div><div class="debug-line">=></div><div class="debug-values">' + _a + '</div><div class="debug-clear"></div>';
								} else {
									var _b = "";
									for (var n in obj[i]) {
										_b += '<div class="debug-names">' + n + '</div><div class="debug-line">=></div><div class="debug-values">' + obj[i][n] + '</div><div class="debug-clear"></div>';
									}
									aArr += '<div class="debug-names">' + m + '</div><div class="debug-line">=></div><div class="debug-values">' + _b + '</div>';
								}
							} else {
								aArr += '<div class="debug-names">' + m + '</div><div class="debug-line">=></div><div class="debug-values">' + obj[i][m] + '</div><div class="debug-clear"></div>';
							}
						}
						subStr += aArr;
						str += '<li><div class="debug-names">' + i + '</div><div class="debug-line">=></div><div class="debug-values">' + subStr + '</div><div class="debug-clear"></div></li>';
					} else {
						for (var m in obj[i]) {
							if (typeof obj[i][m] == "object") {
								if (obj[i][m]instanceof Array) {
									for (var j = 0; j < obj[i][m].length; j++) {
										oimStr += '<div class="debug-names">' + j + '</div>' + '<div class="debug-line">=></div>' + '<div class="debug-values">' + obj[i][m][j] + '</div><div class="debug-clear"></div>';
									}
									subStr = oimStr;
								} else {
									for (var j in obj[i][m]) {
										oimStr += '<div class="debug-names">' + j + '</div>' + '<div class="debug-line">=></div>' + '<div class="debug-values">' + obj[i][m][j] + '</div><div class="debug-clear"></div>';
									}
									subStr = oimStr;
								}
							} else {
								subStr += '<div class="debug-names">' + m + '</div>' + '<div class="debug-line">=></div>' + '<div class="debug-values">' + obj[i][m] + '</div><div class="debug-clear"></div>';
							}
						}
						str += '<li><div class="debug-names">' + i + '</div><div class="debug-line">=></div><div class="debug-values">' + subStr + '</div><div class="debug-clear"></div></li>';
					}
				} else {
					str += '<li><div class="debug-names">' + i + '</div><div class="debug-line">=></div><div class="debug-values">' + obj[i] + '</div><div class="debug-clear"></div></li>';
				}
				ml++;
			}
			type = "Object";
			oLen = ml;
		}
	} else if (obj instanceof Function) {
		str = obj;
		type = "Function";
	}
	result = '<ul class="uls"><li class="debug-obj-info">This is a <span class="debug-obj">'+type+'</span>info  lenght:'+oLen+'</li>' + str + '</ul>';
	var layer = document.createElement("div");
	var box = document.createElement("div");
	var title = document.createElement("div");
	var content = document.createElement("div");
	layer.setAttribute("class","layer");
	layer.setAttribute("id", "debugLayer");
	box.setAttribute("class","debug-box");
	box.setAttribute("id", "debugBox");
	title.setAttribute("id", "debugTitle");
	title.setAttribute("class","debug-title");
	layer.appendChild(box);
	content.setAttribute("id", "debugContent");
	content.setAttribute("class","debug-cs");
	box.appendChild(title);
	box.appendChild(content);
	title.innerHTML = 'Debug Tools ' + version + '<span id="deBugClose" class="debug-close" title="Close Debug">close</span>';
	content.innerHTML = result;
	document.body.appendChild(layer);
	document.getElementById("deBugClose").onclick = function () {
		document.body.removeChild(layer);
	}
	layer.onclick = function(e){
		if(document.all){
			window.event.cancelBubble = true;
		}else{
			e.stopPropagation();
		}
	}
	
	return _deBugStatus_ = 0;
}

 在body里面添加一个层，然后把信息输出来，很直观，个人觉得也很方便，自己经常使用。

 

//测试一下效果
debug.info(navigator);

//嘿嘿，是不是很酷