Question

GOAL ：尝试确保没有任何字段留空，包括单选按钮设置和下拉列表。任何人吗？

HTML

<form action="add_p_c.php" method="post"> 
    Professor<input type="radio" name="addType" />&nbsp;&nbsp;Course<input type="radio" name="addType" /> 
    <br><br>Name: <input type="text" name="name" /><br> 
    Department: <select name="deptName"><option>Department 1</option> <option>Department 2</option></select>
    Email: <input type="text" name="email" /><br>
    <input type="submit" name="submit" /> 
</form>

** PHP（add_p_c.php）**

 <?php
if (isset($_POST['submit'])) {
if (empty($selected_radio)){ echo "You need to select a prof or course";} else(return;)
    $selected_radio = $_POST['addType'];
if (empty($course_prof_name)){ echo "You need to enter a name";} else(return;)
    $course_prof_name = $_POST['name'];
if (empty($select_dep)){ echo "You select a dept";} else(return;)
    $select_dep = $_POST['deptName'];
$email = $_POST['email'] = "myemail@email.com"; 
if(eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$", $email)) { 
  return; 
} 
else { 
  echo "<span color='red;'>Invalid email address.</span>"; 
} 
}
?>

Answer 1

您可以使用if (empty($variable)) {，请记住，任何评估为false的内容（包括数字0）都会被捕获。

PHP doc：http://php.net/manual/en/function.empty.php

Answer 2

按字面意思检查：

if($_POST['foo'] === ""){

Answer 3

为了安全起见，您应该添加某些内容以提高安全性，因为如果您对数据库执行任何查询，则可以获得SQL注入。试试这个：

<?php
if(isset($_POST['submit']){

    $_POST['name']= trim(strip_tags(addslashes($string)));
    $_POST['deptName']= trim(strip_tags(addslashes($string)));
    $_POST['email']= trim(strip_tags(addslashes($string)));

            /* I can't remember if it should be '' or NULL, but some simple testing will let you know which it is*/
    if($_POST['addType'] != ''){
         if($_POST['name'] != ''){
            if($_POST['deptName'] != ''){
                if($_POST['email']) != ''){
                    $selected_radio = $_POST['addType'];
                    $course_prof_name = $_POST['name'];
                    $select_dep = $_POST['deptName'];
                    $email = $_POST['email'] = "myemail@email.com"; 
                    if(eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$", $email)) { 
                        return; 
                    } 
                    else { 
                        echo "<span color='red;'>Invalid email address.</span>"; 
                    } 
                }
                else{
                    // email wasn't set
                }
            }
            else{
                //deptName wasn't set
            }
        }
        else{
            //name wasn't set
        }
    }
    else{
        // add type wasn't set
    }
}
?>

Answer 4

如果您要使用特别大的表单，可能需要查看使用数组和for循环。当我构建了30个字段数组时，嵌套一系列if语句变得非常笨拙，非常快。

我建议你写一个像

这样的快速功能

function validatePost($checkValues)
{
    foreach($checkValues as $value)
    {
        $checked = 0;
        foreach($_POST as $key => $value)
        {
            if($key == $checkValues)
            {
                 $checked = 1;
                 if(empty($value))
                 {
                     return false;
                 }
             }
         }

         if($checked == 0)
         {
             return false;
         }
    }
}

请记住，这不包括任何正则表达式检查，但您可以在中间的foreach循环中添加它。然后在你的代码中排成行，你可以调用该函数：

$checkValues = array('addType', 'deptName', 'email', 'name')
$return = validatePost($checkValues);
if($return == false)
{
     echo "<span color='red;'>Please fill out entire form.</span>"
}
else
{
     return;
}

显然，您可以添加功能以使其更加详细，但这是一个非常基本的验证，可以扩展。

Php验证表格

4 个答案: