js 全选跟反选 _JavaScript

js 全选和反选

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
?<head>
??<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
??<title>Untitled Document</title>
?</head>
?<script>
??//全选
??function selectAll(){
???//首先判断checkbox是否选中
???var checkbox = document.getElementById("checkbox");
???var checkbox1 = document.getElementsByName("checkbox1");
???//如果checkbox选中，checkbox1数组选中
???//如果checkbox不选中，checkbox1数组不选中
???if(checkbox.checked == true){
????for(var i=0; i<checkbox1.length; i++){
?????checkbox1[i].checked = true;
????}
???}else{
????for(var i=0; i<checkbox1.length; i++){
?????checkbox1[i].checked = false;
????}
???}
??}
??//反选
??function selectOpposite(){
???//首先判断checkbox是否选中
???var checkbox = document.getElementById("checkbox");
???var checkbox1 = document.getElementsByName("checkbox1");
???for(var i=0; i<checkbox1.length; i++){
????checkbox1[i].checked = !checkbox1[i].checked;
???}
??}
?</script>
?<body>
??<table border="1">
???<tr>
????<td>
?????全选<input type="checkbox" id="checkbox" name="checkbox" value="0" >
?????反选<input type="checkbox" id="checkbox" name="checkbox" value="0" >
????</td>
????<td>
?????请写入
????</td>
???</tr>
???<tr>
????<td>
?????<input type="checkbox" id="checkbox1" name="checkbox1" value="0">
????</td>
????<td>
?????<input type="text" id="txt1" name="txt1" value="">
????</td>
???</tr>
???<tr>
????<td>
?????<input type="checkbox" id="checkbox1" name="checkbox1" value="1">
????</td>
????<td>
?????<input type="text" id="txt2" name="txt2" value="">
????</td>
???</tr>
???<tr>
????<td>
?????<input type="checkbox" id="checkbox1" name="checkbox1" value="2">
????</td>
????<td>
?????<input type="text" id="txt3" name="txt3" value="">
????</td>
???</tr>
??</table>
?</body>
</html>