<input type="text" id="a" name="textfield" value="111111111111111111111" text="2">为何这样无法输出a的植value 怎么写?
<script language="JavaScript" type="text/JavaScript">
document.write(document.all.a.value)
</script>
<script language="JavaScript" type="text/JavaScript">
document.write(document.all.a.value)
</script>
alert(document.all.a.value);
</script>
alert(document.all.a.value);
</script>写在</body>后面
<HEAD>
<title>WebForm1</title>
</HEAD>
<body MS_POSITIONING="GridLayout">
<form id="Form1" method="post" runat="server">
<input type="text" id="a" name="textfield" value="111111111111111111111" text="2">
</form>
</body>
<script language="JavaScript" type="text/JavaScript">
alert(document.all.a.value);
</script>
</HTML>
alert(document.all.textfield.value);
</script>
<form id="Form1" method="post" runat="server">
<input type="text" name="textfield" value="111111111111111111111"></form>//使用 name<script language="JavaScript">
//代码放在input之后,因为html是顺序加载的,需要等input加载完之后方可引用
document.write(document.all["textfield"].value)//因用方法很多,这只是一种
</script>
</body>
<HEAD>
<title>WebForm1</title>
</HEAD>
<body MS_POSITIONING="GridLayout">
<form id="Form1" method="post" runat="server">
<input type="text" id="a" name="textfield" Text="111111111111111111111">
</form>
</body>
<script language="JavaScript" type="text/JavaScript">
alert(document.all.a.value);
</script>
</HTML>
你调用alert(document.all.a.value);时<input>控件还没加载