如何在Javascript中使文本框成为必填字段 [英] How Do I Make Textbox A Required Field In Javascript

问题描述

我想让我的文本框必填字段ID是BotBootInput我应该把什么放在document.write行

I want make my textbox REQUIRED FIELD id is BotBootInput what should i put in "document.write" line

<script type="text/javascript">
    var a = Math.ceil(Math.random() * 10);
    var b = Math.ceil(Math.random() * 10);
    var c = a + b
    function DrawBotBoot()
    {
        document.write("What is "+ a + " + " + b +"? ");
        document.write("<input id='BotBootInput' type='text' maxlength='2' size='2'/>");
    }
    function ValidBotBoot(){
        var d = document.getElementById('BotBootInput').value;
        if (d == c) return true;
        return false;

    }
    </script>

请帮助我。

PLEASE HELP ME.

推荐答案

你可以使用这个：http://www.w3schools.com/tags/att_input_required.asp [ ^ ] ...

You may use this: http://www.w3schools.com/tags/att_input_required.asp[^]...

您可以将HTML代码用作：

You can use the HTML Code as :

<form action="">
 Username: <input type="text" name="usrname" required="">
<input type="submit">
</input></input></form> 

您可以使用HTML& JavaScript：

You can use the HTML & JavaScript:

<form name="myForm" action=""   önsubmit="return validateForm()" method="post">
 First name: <input type="text" name="fname">
 <input type="submit" value="Submit">
 </form>

<script language="JavaScript">
function validateForm() {
     var x = document.forms["myForm"]["fname"].value;
     if (x == null || x == "") {
         alert("First name must be filled out");
         return false;
     }
 }
</script>

http://www.netmechanic.com/news/vol6/javascript_no4.htm [ ^ ]

http://msdn.microsoft.com/en-us/library/office/aa218652(v=office.11​​).aspx [ ^ ]

http://www.w3schools.com/JS/js_form_validation.asp [ ^ ]

http://www.netmechanic.com/news/vol6/javascript_no4.htm[^]
http://msdn.microsoft.com/en-us/library/office/aa218652(v=office.11).aspx[^]
http://www.w3schools.com/JS/js_form_validation.asp[^]

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