How to use $_POST

Question

I have the following PHP file:

<?php
    echo <<<_END
    <form method='POST' action='index.php' enctpye='multipart/form-data'>
    New Content: <input type='text' name='content'/><br/>
    New Image: <input type="file" name='image' size='10' /><br/>
    Products:
        <select name="filename">
        <option value="product1.txt">Product 1</option>
        <option value="product2.txt">Product 2</option>
        <option value="product3.txt">Product 3</option>
        </select>
    </form> 
    _END;
    echo <<<_END
    <input type="submit" value="Upload"/>
    _END;

    echo $_POST["filename"];
?>

I am getting this error when i try to run this.

Notice: Undefined index: filename in `C:\xampp\htdocs\index.php` on line 18

Sorry, I am new to PHP but should this not echo either product1.txt, product2.txt or product3.txt?

which framework you are using ? It seems you are using some framework.When form will be submited then only you will get required output. — Poonam, May 28 '13 at 11:23

score 4 · Accepted Answer · edited May 23 '17 at 12:05

4

You can get post values only after submitting form,

if(isset($_POST["filename"])){
    echo $_POST["filename"];
}

Or better give name submit or something to your submit button & check,

if(isset($_POST["submit"])){
    echo isset($_POST["filename"]) ? $_POST["filename"] : '';
    echo isset($_POST["content"]) ? $_POST["content"] : '';
    .....
}

Helpful: What does this error mean in PHP?

edited May 23 '17 at 12:05

Community

1
1

answered May 28 '13 at 11:22

Rikesh

26,156
14
79
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You should check the other vars, because users can manipulate your form. – kelunik May 28 '13 at 11:29
even shorter: `if(isset($_POST['submit'], $_POST['filename'], $_POST['content'])) { ...` – kelunik May 28 '13 at 11:46
@Recode - We have to keep some work for user to do himself & learn :) – Rikesh May 28 '13 at 11:49

score 1 · Answer 2 · answered May 28 '13 at 11:23

1

You have to check if it's set:

if(isset($_POST['filename']))
 echo $_POST['filename'];

answered May 28 '13 at 11:23

kelunik

6,750
2
41
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score 0 · Answer 3 · answered May 28 '13 at 11:22

0

You have to try first if the variable is set http://php.net/manual/fr/function.isset.php

answered May 28 '13 at 11:22

PeterFour

329
4
16

How to use $_POST

3 Answers3