使用Javascript比较HTML中的两个输入数字？

本文介绍了使用Javascript比较HTML中的两个输入数字？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我使用Notepad ++创建一个简单的网页，用户在两个数字中键入一个文本框，然后按下一个按钮。当他们按下按钮时会出现一些信息，告诉他们第一个或第二个数字是否更大。我有下面的代码，但不能得到任何东西来。有谁知道最新错误？

$ b $

 <！DOCTYPE html PUBLIC -  // W3C // DTD XHTML 1.0 Strict // EN
 http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd\"> 
 < head> 
< meta http-equiv =content-typecontent =text / html; charset = utf-8/> 
< title>作业10表格< /标题> 
 
< script type =text / javascript> 
 
函数greaterNum（）{
 var value1; 
 var value2; 
 value1 = document.First_num.value; 
 value2 = document.last_num.value; 
 if（value1> value2）{
 alert（'值1大于值2'）; 
 document.body.style.background =orange; 
} 
 
} 
 
 
< / script> 
 
 
< style type =text / css> 
 body {background-color：＃40FF00; 
 margin-left：auto; 
 margin-right：auto; 
宽度：60％; 
} 
 
 #container {
 border：2px纯黄色; 
 padding：20px; 
} 
 
< / style> 
 
< / head> 
 
< body> 
< h1>作业10< / h1> 
 
< div id =container> 
< div class =Num> 
< form> 
< label class =label1>输入值1：< / label> 
< input type =textname =First_numvalue =/> 
< label class =label1>输入值2：< / label> 
< input type =textname =last_numvalue =/> 
< br /> 
< input type =buttonvalue =哪个数字更大？onclick =greaterNum（）; /> 
< / form> 
 
< / body> 
< / html>

解决方案

来自输入的值被检索为字符串，您需要将其转换为数字。试试这个：

  value1 = + document.First_num.value; 
 value2 = + document.last_num.value;

另外，为输入命名时要保持一致性，为什么要为一个和另一个小写字母上限？

I am using Notepad++ to create a simple web page where a user types in two numbers into a text box, and then presses a button. When they press the button something comes up that tells them whether the first or second number is greater. I have the following code but cant get anything to come up. Does anyone know whats wrong?

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8" />
   <title>Assignment 10 Form</title>

    <script type="text/javascript">

        function greaterNum(){
        var value1;
        var value2;
        value1 = document.First_num.value;
        value2 = document.last_num.value;
        if (value1 > value2){
        alert('Value 1 is greater than value 2');
        document.body.style.background = "orange";
        }

    }


</script> 


<style type="text/css">
  body{background-color: #40FF00;
    margin-left: auto;
    margin-right: auto;
    width: 60%;
    }

#container{
    border: 2px solid yellow;
    padding: 20px;
    }

</style>

</head>

<body>
<h1>Assignment 10</h1>

<div id="container">
    <div class="Num">
    <form>
<label class="label1">Enter Value 1:</label>
<input type="text" name="First_num" value=" " />
<label class="label1">Enter Value 2:</label>
<input type="text" name="last_num" value=" " />
<br/>
<input type="button" value=" Which number is greater? " onclick="greaterNum();" />
</form>

</body>
</html>

解决方案

Values from inputs are retrieved as strings, you need to convert it to number. Try this:

value1 = +document.First_num.value;
value2 = +document.last_num.value;

Also, try to be consistent when naming your input, why caps for one and lowercase for the other?

这篇关于使用Javascript比较HTML中的两个输入数字？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！