如例:
<form name="form1" method="post">
<textarea name="textfield" cols="50" rows="3">ffff1</textarea>
<input type="checkbox" name="checkbox1" value="ffff2" />
<input type="checkbox" name="checkbox2" value="ffff3" />
<input type="checkbox" name="checkbox3" value="ffff4" />
</form>
如果选中checkbox2,checkbox3就在增加
<textarea name="textfield" cols="50" rows="3">ffff1,ffff3,ffff4</textarea>如果取沙,就减少,怎样做到
<form name="form1" method="post">
<textarea name="textfield" cols="50" rows="3">ffff1</textarea>
<input type="checkbox" name="checkbox1" value="ffff2" />
<input type="checkbox" name="checkbox2" value="ffff3" />
<input type="checkbox" name="checkbox3" value="ffff4" />
</form>
如果选中checkbox2,checkbox3就在增加
<textarea name="textfield" cols="50" rows="3">ffff1,ffff3,ffff4</textarea>如果取沙,就减少,怎样做到
给每个checkbox添加一个点击时间,点击一下就去比较字符串
<input type="checkbox" onclick="check(this.value)" name="checkbox1" value="ffff2" />
function check(val){
if(str.indexof(val)<0){
orm1.textfield.value=str+ val;
}else{
orm1.textfield.value.replace(val,"");
}
}
2、设置一个js数组,存放3个value,checkbox点击一次就去操作数组,如果是勾选的,就添加值,如果是去掉勾选的,就把那个下标的值去掉,然后遍历数组,取出来,加上textarea原来的值,设进去
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Untitled Page</title> <script language="javascript">
var checkedValue = new Array();
checkedValue.push("ffff1");
function Checked(e) {
if (e.checked) {
if (!checkedValue.exists(e.value)) checkedValue.push(e.value);
}
else {
if (checkedValue.exists(e.value)) checkedValue.remove(e.value);
}
document.getElementById("textfield").value = checkedValue.join(",");
}
Array.prototype.exists = function(value) {
for (var i = 0, l = this.length; i < l; i++) if (this[i] == value) return true;
return false;
}
Array.prototype.remove = function(value) {
for (var i = 0, n = 0, l = this.length; i < l; i++) if (this[i] != value) this[n++] = this[i];
this.length -= 1;
}
</script></head>
<body>
<form id="form1" runat="server">
<div>
<textarea name="textfield" id="textfield" cols="50" rows="3">ffff1</textarea>
<input type="checkbox" name="checkbox1" value="ffff2" onclick="Checked(this);" />
<input type="checkbox" name="checkbox2" value="ffff3" onclick="Checked(this);" />
<input type="checkbox" name="checkbox3" value="ffff4" onclick="Checked(this);" />
</div>
</form>
</body>
</html>