Javascript html表单中的年龄验证有问题
我想打印出来的段落标记输入正常,只会闪烁一秒钟,然后消失Javascript html表单中的年龄验证有问题,javascript,html,forms,validation,Javascript,Html,Forms,Validation,我想打印出来的段落标记输入正常,只会闪烁一秒钟,然后消失 <!DOCTYPE html> <html> <head> <meta charset='utf-8'> <meta http-equiv='X-UA-Compatible' content='IE=edge'> <title>HOMEWORK</title> <meta name='viewport' content
<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8'>
<meta http-equiv='X-UA-Compatible' content='IE=edge'>
<title>HOMEWORK</title>
<meta name='viewport' content='width=device-width, initial-scale=1'>
</head>
<body>
<h1 style="text-align:center">FORM FILL</h1>
<p>Kindly fill in the following details as mentioned below : </p>
<form name="FORM" onsubmit="checkform()">
<!---- <label for="FName">Name :</label><br>
<input type="text" id="FName" name="FName"><br><br>--->
<label for="Age">Age :</label><br><br>
<input type="text" id="Age" name="Age"><br><br>
<input type="button" value="Submit">
</form><br><br>
<p id="demo"></p>
<script>
function checkform()
{
var x, text;
x = document.forms["FORM"]["Age"].value;
if (x<1||x>100||x==''||isNaN(x))
{
alert("Invalid Age !!!");
text = "Input not valid";
// return false;
}
else
{
text = "Input OK";
// return true;
}
document.getElementById("demo").innerHTML = text;
}
</script>
</body>
</html>
作业
填表
请填写以下详细信息,如下所述:
年龄:
函数检查表()
{
变量x,文本;
x=文件.forms[“FORM”][“Age”].值;
如果(x100 | | x=''| | isNaN(x))
{
警告(“无效年龄!!!”;
text=“输入无效”;
//返回false;
}
其他的
{
text=“输入确定”;
//返回true;
}
document.getElementById(“demo”).innerHTML=text;
}
有人能告诉我我做错了什么吗?
验证表单的最短方法是什么?您需要防止重定向页面,对代码做了一些更改,请检查一下:
<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8'>
<meta http-equiv='X-UA-Compatible' content='IE=edge'>
<title>HOMEWORK</title>
<meta name='viewport' content='width=device-width, initial-scale=1'>
</head>
<body>
<h1 style="text-align:center">FORM FILL</h1>
<p>Kindly fill in the following details as mentioned below : </p>
<form name="FORM" onsubmit="return mySubmitFunction(event)">
<!---- <label for="FName">Name :</label><br>
<input type="text" id="FName" name="FName"><br><br>--->
<label for="Age">Age :</label><br><br>
<input type="text" id="Age" name="Age"><br><br>
<input type="submit" value="Submit">
</form><br><br>
<p id="demo"></p>
<script>
function mySubmitFunction(e) {
e.preventDefault();
try {
checkform();
} catch (e) {
throw new Error(e.message);
}
return false;
}
function checkform()
{
var x, text;
x = document.forms["FORM"]["Age"].value;
if (x<1||x>100||x==''||isNaN(x))
{
alert("Invalid Age123 !!!");
text = "Input not valid";
// return false;
}
else
{
text = "Input OK";
// return true;
}
document.getElementById("demo").innerHTML = text;
}
</script>
</body>
</html>
作业
填表
请填写以下详细信息,如下所述:
年龄:
函数mySubmitFunction(e){
e、 预防默认值();
试一试{
checkform();
}捕获(e){
抛出新错误(例如消息);
}
返回false;
}
函数检查表()
{
变量x,文本;
x=文件.forms[“FORM”][“Age”].值;
如果(x100 | | x=''| | isNaN(x))
{
警告(“无效年龄123!!!”;
text=“输入无效”;
//返回false;
}
其他的
{
text=“输入确定”;
//返回true;
}
document.getElementById(“demo”).innerHTML=text;
}
希望这有帮助