jQuery 全选与不全选 Jquery each

<script type="text/javascript"> ???????jQuery(function () {　　　　　　 ?//当全选点击的时候 ???????????jQuery("thead tr th:first input").click(function () { ???????????????//将要需要全选的复选框的选中状态同 全选复选框的选中状态一样 ???????????????jQuery("tbody tr td ?input").attr("checked", this.checked); ???????????});　　　　　　 ?//出全选以外的复选框 ???????????jQuery("tbody tr td ?input").click(function () {　　　　　　　　　//如果当前复选框为false时 ?全选的复选框将不被选中 ???????????????if (!this.checked) {　　　　　　　　　　　　//设置全选的复选框为不选中 ???????????????????jQuery("thead tr th:first input").attr("checked", this.checked); ???????????????} else {　　　　　　　　　　　　//判断其他复选框是否全部选中 ?如果全为选中状态则将 全选复选框设置为选中状态true否则设置为false ???????????????????if (jQuery("tbody tr td ?input:checked").length == jQuery("tbody tr td ?input").length) { ???????????????????????jQuery("thead tr th:first input").attr("checked", this.checked); ???????????????????} ???????????????} ???????????}) ???????})</script>

最终效果

//html片段<div id="allcheckbox"> ?<input type="checkbox" class="checkall" style="width: 20px; height: 20px" /></div><div id="childrencheckbox"> ?<input type="checkbox" class="checkall" style="width: 20px; height: 20px" /> ?<input type="checkbox" class="checkall" style="width: 20px; height: 20px" /> ?<input type="checkbox" class="checkall" style="width: 20px; height: 20px" /> ?<input type="checkbox" class="checkall" style="width: 20px; height: 20px" /></div>

//js代码片段//注意：在这执之前要引入jquery的js额<script type="text/javascript"> ???????jQuery(function () { ???????????jQuery("#allcheckbox input").click(function () { ???????????????jQuery("#childrencheckbox ?input").attr("checked", this.checked); ???????????}); ???????????jQuery("#childrencheckbox ?input").click(function () { ???????????????if (!this.checked) { ???????????????????jQuery("#allcheckbox input").attr("checked", this.checked); ???????????????} else { ???????????????????if (jQuery("#childrencheckbox ?input:checked").length == jQuery("#childrencheckbox ?input").length) { ???????????????????????jQuery("#allcheckbox input").attr("checked", this.checked); ???????????????????} ???????????????} ???????????}) ???????})</script>

//id保存在复选框的pid属性中var intid = "";jQuery("tbody tr td ?input:checked").each(function (index, element) { ?intid = intid + jQuery(this).attr("pid") + ",";})if (intid == "") { ?alert("没有选中数据项"); ?return;}

//循环数据var arr1 = [ "one", "two", "three", "four", "five" ];$.each(arr1, function(){alert(this);});