Question

您好，我是php初学者，我的代码存在以下问题，我需要添加2个数字并将结果作为第3个数字（总和）回显。总和数字不得在单击“提交”按钮之前显示，仅这两个数字的输入框，当显示总和时，必须隐藏两个输入框，并且只显示总和

<html>  
<body>  
    <form method="post" id="form1">  
        First Number:  
        <input type="text" name="number1" /><br>  
        Second Number:  
        <input type="text" name="number2" /><br>  
        <input  type="submit" name="submit" value="Add" >  
    </form>  


    <?php 
    $number1 = $_POST['number1'];  
    $number2 = $_POST['number2'];  
    $sum =  $number1+$number2;     
    echo "Sum = ".$sum;
    ?>

    </script>  
</body>  
</html>

Answer 1

您需要使用isset函数进行检查，以了解是否提交了表单。像下面一样，

<body>  
   <?php if( !isset($_POST['submit'])){ ?> 
   <form method="post" id="form1">  
        First Number:  
        <input type="text" name="number1" /><br>  
        Second Number:  
        <input type="text" name="number2" /><br>  
        <input  type="submit" name="submit" value="Add" >  
    </form>  
    <?php } ?>

    <?php 
    if(isset($_POST['submit'])){
       $number1 = $_POST['number1'];  
       $number2 = $_POST['number2'];  
       $sum =  $number1+$number2;     
       echo "Sum = ".$sum;
    }
    ?>

    </script>  
</body>  
</html>

显示/隐藏表单提交中的元素

1 个答案: