PHP 不接收来自 post 表单的值

Question

CASE 1

if i put this , i can´t receive the end value from input

<?php echo $_POST[tester-test-t]; ?>

<form action="" method="post"> <input type="text" name="tester-test-t" value="" /> <input type="submit" name="Send" value="Sender" /> </form>

CASE 2

if i put this i can receive value from form

<?php echo $_POST['tester-test-t']; ?>

<form action="" method="post"> <input type="text" name="tester-test-t" value="" /> <input type="submit" name="Send" value="Sender" /> </form>

CASE 3

And finally if i put this , also i can received the value from POST form , as you can see i puto "_" and not the same as in the case 1 "-"

echo $_POST[tester_test_t]; 

<form action="" method="post"> <input type="text" name="tester-test-t" value="" /> <input type="submit" name="Send" value="Sender" /> </form>

The question it´s about , which it´s the problem for not receive the value from post form in the case 1 and yes , in the other cases with '' and with "-"

Regards and thank´s

Answer 1

Case 1:

tester-test-t means

take value of constant tester , substract value of constant test , substract value of constant t .

The result of substraction will be the key in a $_POST array.

Do you have such constants in your code? Surely, you don't .

Case 2:

'tester-test-t' is just a string. And string key 'tester-test-t' exists in your $_POST

Case 3:

tester_test_t is considered a constant again. Do you have constant tester_test_t defined? Surely, you don't .

And to understand what's going wrong in your code - use error_reporting (thanks @Fred -ii-)

Answer 2

It's likely to be something to do with character encoding, and how the - gets treated as it is passed into an http request as the form gets submitted. The - is likely getting encoded in a certain way and causing you problems.

A simple solution is getting rid of the hyphens in your field name, so change name="tester-test-t" to something like name="TesterTestT".

Personally I prefer to specify an action="" with the name of another .php script to do the processing of the form. I find submitting the form back to itself can get confusing.

Rgds