php - POST 表单后 php 脚本中未定义的索引

Question

$username = $_POST['username'];
$ppassword = $_POST['password'];
$password = md5("$ppassword");

这是代码，我收到此错误

Notice: Undefined index: username in C:\wamp\www\php\compare.php on line 14
Call Stack
#   Time    Memory  Function    Location
1   0.0004  250440  {main}( )   ..\lognet.php:0
2   0.0007  260000  include( 'C:\wamp\www\php\compare.php' )    ..\lognet.php:3


Notice: Undefined index: password in C:\wamp\www\php\compare.php on line 15
Call Stack
#   Time    Memory  Function    Location
1   0.0004  250440  {main}( )   ..\lognet.php:0
2   0.0007  260000  include( 'C:\wamp\www\php\compare.php' )    ..\lognet.php:3

这是表格：

<form name="form1" method="post" action="compare.php">
<strong><input id="close" type="button" value="X"                                     
onclick="getElementById('loginbox').style.display = 'none'">Member Login</strong></br>
Username:<input name="username" type="text" id="username"></br>
Password:<input name="password" type="password" id="password">
&nbsp;
&nbsp;&nbsp;
&nbsp;&nbsp;</br>
<input type="submit" name="Submit" value="Login">
</form>

我让它工作但是当他们将 php 更新到 5.4.12 时它停止了，我不得不改变它。

Answer 1

You can do something like this -

$username = isset($_POST['username']) ? $_POST['username'] : '';
$password = isset($_POST['password']) ? md5($_POST['password']) : '';

Answer 2

使用 isset() 函数来检查变量集与否？

$username = isset($_POST['username']) ? $_POST['username'] : '';

$password = isset($_POST['password']) ? md5($_POST['password']) : '';

// 您的 html 代码放在这里并确保您的 html文本字段名称应与$_POST['variable_name']匹配

Answer 3

例如，如果您在 html 表单的同一页面中有此代码，则需要：

if(isset($_POST['password']) && isset($_POST['username'])){

$username = $_POST['username'];
$ppassword = $_POST['password'];
$password = md5("$ppassword");

}

如果您在其他页面中有此代码，请确认您是否收到帖子值

echo $_POST['username'];
echo $_POST['password'];

如果不是你设置错误你的输入

<form action="somepage.php" method="post">

<input type="text" name="username" value="" />

<input type="password" name="password" value="" />

<input type="submit" name="submit" value="Submit" />

</form>