JavaScript中浮点和非空的验证_Javascript_Html_Css_Web_Bootstrap 4

JavaScript中浮点和非空的验证

javascript html css web bootstrap-4

JavaScript中浮点和非空的验证,javascript,html,css,web,bootstrap-4,Javascript,Html,Css,Web,Bootstrap 4,我对web开发是一个新手，我从基本应用程序开始。我正在制作一个简单的网页来添加两个数字，并尝试执行一些基本的验证，以确保输入字段不能为空，并且输入只能是一个浮点数 My index.html： <!doctype html> <html lang="en"> <head>  <meta charset="utf-8"> <meta name="viewp

我对web开发是一个新手，我从基本应用程序开始。我正在制作一个简单的网页来添加两个数字，并尝试执行一些基本的验证，以确保输入字段不能为空，并且输入只能是一个浮点数

My index.html：

<!doctype html>
<html lang="en">
<head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
    <link rel="stylesheet" type="text/css" href="styles.css">
    <link href="https://fonts.googleapis.com/css2?family=Merriweather&display=swap" rel="stylesheet">
    <title>Add Two Numbers</title>
</head>
<body>
    <form class="container center_div topSpacing">
        <h1 id="Title" class="text-center">Add Two Numbers</h1> 
        <div class="form-group">
        <label for="Num1">First Number</label>
        <input type="text" class="form-control" id="Num1" placeholder="Enter First Number">
        </div>
        <div class="form-group">
        <label for="Num2">Second Number</label>
        <input type="text" class="form-control" id="Num2" placeholder="Enter Second Number">
        </div>
        <div class="text-center">
            <button onclick="result()" type="button" class="btn btn-outline-success">Evaluate</button>
        </div>
    </form>
    <br>

    <h1 id="Title2" class="text-center"></h1>

    <script src="https://code.jquery.com/jquery-3.4.1.slim.min.js" integrity="sha384-J6qa4849blE2+poT4WnyKhv5vZF5SrPo0iEjwBvKU7imGFAV0wwj1yYfoRSJoZ+n" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js" integrity="sha384-wfSDF2E50Y2D1uUdj0O3uMBJnjuUD4Ih7YwaYd1iqfktj0Uod8GCExl3Og8ifwB6" crossorigin="anonymous"></script>
    <script type="text/javascript" src="index.js"></script>
</body>
</html>

JavaScript代码没有执行验证和求和

改变这个

function validate() {
if(var1 == "" || var2 == "")
    return false;
return true;

}

到

这应该行得通。

简单的解决方案是将输入字段设置为键入数字

 <input type="number" class="form-control" id="Num1" placeholder="Enter First Number">
        </div>

 <input
          type="number"
          class="form-control"
          id="Num2"
          placeholder="Enter Second Number"
        />

var1

和

var2

是对元素的引用，如果这些元素存在，则始终传递

if

。

function validate() {
if(var1.value == "" || var2.value == "")
    return false;
else
    return true;
}

 <input type="number" class="form-control" id="Num1" placeholder="Enter First Number">
        </div>

 <input
          type="number"
          class="form-control"
          id="Num2"
          placeholder="Enter Second Number"
        />

 function validate() {
  const reg = /\-?\d+\.\d+/g;
  if (
    var1.value !== "" &&
    var2.value !== "" &&
    var1.value.match(reg) &&
    var2.value.match(reg)
  ) {
    return true;
  }
  return false;
}