Passing user's input value to a variable

[Hall of Famer]

Well this may sound confusing. I tried to findways to allow users to input an integer value and then assign it to a variable called $quantity, but all I could find from the internet was the usage of forms. Do I have to use forms, or can I just try this this simple syntax:

 

$quantity = "<input name='quantity' type='text' id='quantity' size='3' maxlength='3'>";

 

If I do have to use forms, then how can I ever assign user's input value to a variable? Please help.

[dragon_sa]

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<?php
if ($_SERVER['REQUEST_METHOD'] == 'POST' && isset($_POST['quantity']) {
if (is_int($_POST['quantity']) { $quantity= $_POST['quantity']; }
}
?>
<form method='post' action=''>
<input name='quantity' type='text' id='quantity' size='3' maxlength='3' />
<input type='submit'  name='submit' value='submit' />
</form>

 

Then you can use the variable $quantity anywhere on your page

[Hall of Famer]

umm so the simple syntax wont work? Is the part submit important? What does it do?

[dragon_sa]

The submit is a button that sends your form data back to this page for processing

 

$_SERVER['REQUEST_METHOD'] == 'POST' && isset($_POST['quantity']

 

checks for the form being submitted and also that the value of quantity has been set

 

is_int($_POST['quantity']

 

checks to make sure that the value of quantity is an integer

 

$quantity= $_POST['quantity'];

 

sets the variable $quantity to the integer value submitted.

 

For it to work you need to have all the parts of the form as shown.

[lazylodr]

$quantity = "<input name='quantity' type='text' id='quantity' size='3' maxlength='3'>";

All you are doing here is assigning the value "<input name='quantity' type='text' id='quantity' size='3' maxlength='3'>" to the variable $quantity in PHP on the server. This has nothing to do with data from a user. If you want data from a user, you must use forms and their submitted values (using $_GET, $_POST variables depending on the form's method attribute) from the request as outlined above.

 

The <input type="submit" /> renders a submit button on the form so the user can send the data back to the server.

[Pikachu2000]

is_int($_POST['quantity']

 

checks to make sure that the value of quantity is an integer

 

is_int on form data will never return TRUE since all form data is, by default, string type. In this case, since a whole number is expected, ctype_digit would be appropriate to validate it.

 

$quantity= $_POST['quantity'];

 

sets the variable $quantity to the integer value submitted.

 

That would need to be $quantity = (int) $_POST['quantity']; to cast the value as an integer.

[Hall of Famer]

Thank you so much for the reply guys, I will give a try tomorrow and see if this works.