php 检查文本框是否为空？
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Checking Whether a textbox is empty?
提问by Duncan Palmer
Hey guys i'm trying to make a php script check whether or not the text boxes are empty, i am using the below code.
嘿伙计们，我正在尝试使用 php 脚本检查文本框是否为空，我正在使用以下代码。
<?php
$dbname = $_POST['db_name'];
$dbuser = $_POST['db_user'];
$dbpass = $_POST['db_pass'];
$username = $_POST['username'];
$password = $_POST['password'];
if($dbname == "" || $dbuser == "" || $dbpass == "" || $username == "" || $password == "")
{
Echo("Missing Information!");
}else{
Echo("Success!");
}
?>
Below is my form code:
下面是我的表单代码：
<form method="post" style="padding-left: 50px" action="install_submit.php">
<h2>Database connection settings</h2>
<label for="db_name">Database name:</label>
<input type="textbox" id="db_name" name="db_name" /><br/>
<label for="db_user">Database username:</label>
<input type="textbox" id="db_user" name="db_user" /><br/>
<label for="db_pass">Database password:</label>
<input type="password" id="db_pass" name="db_pass" /><br/>
<h2>CPanel settings</h2>
<label for="username">Username:</label>
<input type="textbox" id="username" name="username" /><br/>
<label for="password">Password:</label>
<input type="password" id="password" name="password" /><br/>
<input type="submit" name="submit_install" value="Install" />
</form>
With that it always returns "Missing Information!" even when all the text boxes are filled in.
有了它，它总是返回“缺少信息！” 即使所有的文本框都填满了。
What am i doing wrong?
我究竟做错了什么？
回答by Madara's Ghost
Use empty()instead,
使用empty()替代，
if (empty($dbname) || empty($dbuser) || empty($dbpass) || empty($username) || empty($password)) {
//Empty
}
else {
//Not Empty
}
Check to see that the namesof the inputs are correct as well.
检查输入的names是否也正确。
回答by broch
For debugging try to do a
对于调试尝试做一个
print_r($_POST);
to see what you actually receive in the $_POST variable and then try one comparison at a time in your if statement. Maybe it makes you see behind the scene.
查看您在 $_POST 变量中实际收到的内容，然后在 if 语句中一次尝试一个比较。也许它会让你看到幕后。
回答by jay.jivani
Replace this & check whether you get all parameters value or not.
替换它并检查您是否获得所有参数值。
<?php
$dbname = $_POST['db_name'];
$dbuser = $_POST['db_user'];
$dbpass = $_POST['db_pass'];
$username = $_POST['username'];
$password = $_POST['password'];
echo "<pre>";
print_r($_POST);
echo "</pre>";
die();
if($dbname == "" || $dbuser == "" || $dbpass == "" || $username == "" || $password == ""){
echo("Missing Information!");
}else{
echo("Success!");
}
?>
回答by Sanket
To check the posted data u can use isset().
要检查发布的数据，您可以使用isset()。
Determine if a variable is set and is not NULL
确定变量是否已设置且不为 NULL
if(!isset($dbname) || trim($dbname) == '')
{
echo "You did not fill out the required fields.";
}
trim()keyword remove white spaces which are ignored by empty().
trim()关键字删除被忽略的空格empty()。
