JavaScript實戰之購物車案例

這個是通過網上視頻案例學習，然後，自己想整理一下頁面書寫流程文檔。

show樣式：

HTML代碼結構+CSS結構

初始化css樣式：

	* {
	    margin: 0;
	    padding: 0;
	}
	a {
	    color: #666;
	    text-decoration: none;
	}
	body {
	    padding: 20px;
	}

此頁面主要分爲兩個部分：商品表格部分+合計結算等的頁腳部分

對應代碼：

表格

表格總體樣式：

table {
    border-collapse: collapse;     //邊框合併爲單一邊框
    border-spacing: 0;             //相鄰單元格邊框間距，因collapse的存在，無影響
    border: 0;                     //邊框寬度，在此處沒有影響
    text-align: center;
    width: 937px;
}

表格頭部：

對應樣式：

th, td {
    border: 1px solid #CADEFF;
}
th {
    background: #e2f2ff;
    border-top: 3px solid #a7cbff;
    height: 30px;
}

表格主體內容部分
每一行代碼都差不多就是圖片文字數字更改一下

<tr>
	<td class="checkbox"><input type="checkbox" class="check-one check" /></td>
	<td class="goods"><img src="img/1.jpg" alt="" /><span>用JS實現購物車特效</span></td>
	<td class="price">5999.88</td>
	<td class="count">
		<span class="reduce"></span>
		<input class="count-input" type="text" value="1" />
		<span class="add">+</span>
	</td>
	<td class="subtotal">5999.88</td>
	<td class="operation"><span class="delete">刪除</span></td>
</tr>

對應的樣式：

td {
    padding: 10px;
    color: #444;
}
tbody tr:hover {
    background: RGB(238,246,255);
}
.checkbox {
    width: 60px;
}
.goods {
    width: 300px;
}
.goods span {
    width: 180px;
    margin-top: 20px;
    text-align: left;
    float: left;
}
.price {
    width: 130px;
}
.count {
    width: 90px;
}
.count .add, .count input, .count .reduce {
    float: left;
    margin-right: -1px;
    position: relative;
    z-index: 0;
}
.count .add, .count .reduce {
    height: 23px;
    width: 17px;
    border: 1px solid #e5e5e5;
    background: #f0f0f0;
    text-align: center;
    line-height: 23px;
    color: #444;
}
.count .add:hover, .count .reduce:hover {
    color: #f50;
    z-index: 3;
    border-color: #f60;
    cursor: pointer;
}
.count input {
    width: 50px;
    height: 15px;
    line-height: 15px;
    border: 1px solid #aaa;
    color: #343434;
    text-align: center;
    padding: 4px 0;
    background-color: #fff;
    z-index: 2;
}
img {
    width: 100px;	
    height: 80px;
    /*border: 1px solid #ccc;*/
    margin-right: 10px;
    float: left;
}
.operation {
    width: 80px;
}
.operation span:hover, a:hover {
    cursor: pointer;
    color: red;
    text-decoration: underline;
}

foot部分

HTML:

<div class="foot" id="foot">
   <label class="fl select-all"><input type="checkbox" class="check-all check"/>&nbsp;全選</label>
   <a class="fl delete" id="deleteAll" href="javascript:;">刪除</a>
   <div class="fr closing">結 算</div>
   <div class="fr total">合計：￥<span id="priceTotal">0.00</span></div>
   <div class="fr selected" id="selected">已選商品
     <span id="selectedTotal">0</span>件
     <span class="arrow up">︽</span>
     <span class="arrow down">︾</span>
   </div>
   <div class="selected-view">
       <div id="selectedViewList" class="clearfix">
           <!--<div><img src="images/1.jpg"><span>取消選擇</span></div>-->
       </div>
       <span class="arrow">◆<span>◆</span></span>
   </div>
</div>

CSS:

.foot {
    width: 935px;
    margin-top: 10px;
    color: #666;
    height: 48px;
    border: 1px solid #c8c8c8;
    background-color: #eaeaea;
    background-image:linear-gradient(RGB(241,241,241),RGB(226,226,226));
    position: relative;
    z-index: 8;
}
.foot div, .foot a {
    line-height: 48px;
    height: 48px;
}
.foot .select-all {
    width: 100px;
    height: 48px;
    line-height: 48px;
    padding-left: 5px;
    color: #666;
}
.foot .closing {
    border-left: 1px solid #c8c8c8;
    width: 100px;
    text-align: center;
    color: #000;
    font-weight: bold;
    background: RGB(238,238,238);
    cursor: pointer;
}
.foot .total{
    margin: 0 20px;
    cursor: pointer;
}
.foot  #priceTotal, .foot #selectedTotal {
    color: red;
    font-family: "Microsoft Yahei";
    font-weight: bold;
}
.foot .selected {
    cursor: pointer;
}
.foot .selected .arrow {
    position: relative;
    top:-3px;
    margin-left: 3px;
}
.foot .selected .down {
    position: relative;
    top:3px;
    display: none;
}
 .show .selected .down {
    display: inline;
}
 .show .selected .up {
    display: none;
}
.foot .selected:hover .arrow {
    color: red;
}
.foot .selected-view {
    width: 935px;
    border: 1px solid #c8c8c8;
    position: absolute;
    height: auto;
    background: #ffffff;
    z-index: 9;
    bottom: 48px;
    left: -1px;
    display:none;
}
.show .selected-view {
    display: block;
}
.foot .selected-view div{
    height: auto;
}
.foot .selected-view .arrow {
    font-size: 16px;
    line-height: 100%;
    color:#c8c8c8;
    position: absolute;
    right: 330px;
    bottom: -9px;
}
.foot .selected-view .arrow span {
    color: #ffffff;
    position: absolute;
    left: 0px;
    bottom: 1px;
}
#selectedViewList {
    padding: 20px;
    margin-bottom: -20px;
}
#selectedViewList div{
    display: inline-block;
    position: relative;
    width: 100px;
    height: 80px;
    border: 1px solid #ccc;
    margin: 10px;
}
#selectedViewList div span {
    display: none;
    color: #ffffff;
    font-size: 12px;
    position: absolute;
    top: 0px;
    right: 0px;
    width: 60px;
    height: 18px;
    line-height: 18px;
    text-align: center;
    background: RGBA(0,0,0,.5);
    cursor: pointer;
}
#selectedViewList div:hover span {
    display: block;
}

開始添加JS部分代碼

添加window.onload事件，控制js在頁面渲染完成後加載。

控制瀏覽器的兼容性getElementsByClassName：

//瀏覽器兼容性
if(!document.getElementsByClassName){
	document.getElementsByClassName = function(cls){
		var ret = [];
		var els = document.getElementsByTagName('*');
		for(var i = 0,len = els.length;i<len;i++){
			hasClass(els[i],cls);
			function hasClass(element,cls){
				if((' ' + element.className + ' ').indexOf(' '+cls+' ') > -1){
					ret.push(element);
				}
			}
		}
		return ret;
	}
}	
//獲取某些對應的dom元素
	var carTable = document.getElementById('cartTable');
	var tr = carTable.children[1].rows;   //rows：表格元素特有的屬性，存放節點所有tr元素
	var checkInputs = document.getElementsByClassName('check');
	var checkAllInputs = document.getElementsByClassName('check-all');
	var selectedTotal = document.getElementById('selectedTotal');
	var priceTotal = document.getElementById('priceTotal');
	var selected = document.getElementById('selected');
	var foot = document.getElementById('foot');
	var selectedViewList = document.getElementById('selectedViewList');
	var deleteAll = document.getElementById('deleteAll');

單選框和全選框的關聯控制

選擇框分爲單選框和全選框。
設計思路：
點擊全選框，則全部選擇框都會勾選；
在全選的情況下，若取消選擇任意一個選擇框，都會使得全選框取消選擇；
若在未全選情況下，任意點擊非全選框，則點擊的選擇框勾選；
若此情況（未全選）下，除全選框外的選框全部選擇，則默認自動勾選全選框【這部分代碼是我自己寫的，代碼應該還是可以有優化的地方的】。

//選擇框和全選框
for(var i=0,len=checkInputs.length;i<len;i++){
	checkInputs[i].onclick=function(){
		//判斷當前點擊的對象是否是全選框，若是，所有選框狀態同點擊的全選框狀態保持一致
		if(this.className == 'check-all check'){
			for(var j=0;j<checkInputs.length;j++){
				checkInputs[j].checked=this.checked;
			}
		}
		//若當前點擊的選擇框爲未選狀態時，將所有的全選框狀態置爲未選狀態
		else if(this.checked==false){
			for(var k=0;k<checkAllInputs.length;k++){
				checkAllInputs[k].checked = false;
			}
		}
		//當前選擇框點擊狀態爲選中時，判斷是否除全選框外，所有的選框都是選中狀態
		else if(this.checked==true){
			for(var l=0;l<checkone.length;l++){
				if(checkone[l].checked==false){
					return;
				}
				if(l==checkone.length-1){
					for(var k=0;k<checkAllInputs.length;k++){
						checkAllInputs[k].checked = true;
					}
				}
			}
		}
	}
}