把form表单的<form name="form1" method="post" action="addBook2.jsp" onSubmit="return checkdata()>....</form>
函数改成
<script language = "javascript">
function checkdata()
{
if((form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return false;
}
}
</script>
函数改成
<script language = "javascript">
function checkdata()
{
if((form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return false;
}
}
</script>
http://expert.csdn.net/Expert/topic/2459/2459617.xml?temp=.7946436
function checkdata()
{
if((document.form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return false;
}
document.form1.submit();
return true;
}
</script>
<script language = "javascript">
function checkdata()
{
if((document.form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return false;
}
document.form1.submit();
}
</script>
这句话有问题,你只有1个form.根本没有形成数组。所以此法不成立
用form1代替
多加一个隐藏TEXT
<input type="button" name="Submit1" value="添 加" onClick="javascript:checkdata(s1)">
<input type="hidden" name="hidValue" value="">
不是提交按钮就是一般的按钮。checkdate()如下
用
String str =request.getParameter("hidValue")得到他的直
<script language = "javascript">
function checkdata()
{
if((form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return;
}
document.form1.hidValue.value = s1;
document.forms[0].submit();
}
</script><form action ="my.jsp" Mothod = "post">
<%
if (str==null)
.........
%>
</form>
多了个(
function CheckForm()
{
askmsg = "填写的书名正确无误,可以送出了吗!?"
if (document.form1.booknameBox.value.length == 0) {
alert("请输入书名.");
document.form1.booknameBox.focus();
return false;
}
return confirm(askmsg)
return true;
}
</script>
function checkdata()
{
if((form1.booknameBox.value =="" )
{
alert("没有输入书名")
//form1.booknameBox.focus();
return false;
}
else return true; }
</script><form name="form1" method="post" action="addBook2.jsp" onSubmit="return checkdata()">....<input type="Submit" name="Submit1" value="添 加" ></form>
<script language = "javascript">
function jianyan(form1)
{
if(form1.book.value =="" )
{
alert("没有输入书名");
form1.book.focus();
return false;
}
else
return true; }
</script><html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>无标题文档</title>
</head><body>
<form name="form1" method="post" action="jsp.jsp" onSubmit="return jianyan(this)">
<p>
<input type="text" name="book">
</p>
<p><input type="Submit" name="Submit" value="添 加" ></p></form>
</body>
</html>
<script language = "javascript">
function jianyan() { if (form1.book.value =="" ) {
alert("没有输入书名");
form1.book.focus();
return;
}
document.forms[0].action="addBook2.jsp";
document.forms[0].submit();
}
</script><html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>无标题文档</title>
</head>
<body>
<form id="form1" name="form1" method="post">
<input type="text" name="book" id="book"><br>
<input type="button" name="Submit" onClick="jianyan(this)" value="添 加">
</form>
</body>
</html>
如果用提交按钮就需要用<form ..... onsubmit = "return checkform()">
如果使用一般按钮需要<input type = "button" name = "submit" onclick = "checkdata()">
<script language = "javascript">
function checkform(form1)
{
if(form1.book.value =="" )
{
alert("没有输入书名");
form1.book.focus();
return false;
}
else
{
return true;
}
}
</script>
<script language = "javascript">
function checkdata(form1)
{
if(form1.book.value =="" )
{
alert("没有输入书名");
form1.book.focus();
}
else
{
form1.submit();
}
}
</script>