Smarty标签PHP isset声明

Question

I am using smarty tags with php and my question / issue is regarding the !isset functionality. To start with, here is how I create and assign my two arrays. Then I use a SMarty IF statement to compare the conditions, and if the conditions are met, either display or do not display the HTML

The first array gets created from the database, is assigned as a Smarty variable.

{section name=cart loop=$cart}
{/section}

The second array is also pulled from the database, but I am assigning this array through Smarty capture:

{capture name='donate' assign='donate'}
{/capture}

Once the arrays are assigned, here is the if statement:

{if $cart[cart].Program == TT && !isset($donate)}
<td>Make a difference. Donate $10.00 to the ASPCA</td>
{/if}

The HTML still will be displayed, even if the $donate array is not set. Appreciate any insight to point out what I may be doing wrong

Answer 1

{capture name='donate' assign='donate'}
{/capture}
{$donate|var_dump}

will give you

string(0) "" 

since only isset(null) === false, you may want to change your expression to

{if $cart[cart].Program == TT && $donate}

or !empty($donate), if you prefer.