<input type="checkbox" id="c1">全選/全不選<br>興趣愛好：<br><input type="checkbox" name="interst" value="basketball">籃球<input type="checkbox" name="interst" value="football">足球<input type="checkbox" name="interst" value="bedminton">羽毛球<br><input type="button" id="b1" value="全選"><input type="button" id="b2" value="全不選"><input type="button" id="b3" value="反選"><input type="button" id="b4" value="顯示">

$("#c1").click(function(){if(this.checked){  $("input[name='interst']").attr("checked","checked");}else{  //$("input[name='interst']").attr("checked",""); //等價于  $("input[name='interst']").removeAttr("checked");}});$("#b1").click(function(){  $("input[name='interst']").attr("checked","checked");});$("#b2").click(function(){  $("input[name='interst']").attr("checked","");});$("#b3").click(function(){  $("input[name='interst']").each(function(){  if(this.checked){    this.checked="";  }else{    this.checked="checked";  }  });});$("#b4").click(function(){$("input[name='interst']:checked").each(function(){  alert(this.value);});});