P粉4079362812023-09-02 10:10:56
Based on your question above, I think you want to check if a variable is set with a given value. In your case, try using @if(isset($a_string_name)).
We usually use two PHP methods to check variables.
How to check whether a variable is defined in PHP? The isset() function checks if a variable is set, which means the variable must be declared and not NULL. The function returns true if the variable exists and is not NULL, false otherwise.
How to check if a given variable is empty? The empty() function checks whether a variable is empty. The function returns false if the variable exists and is not empty, otherwise it returns true. The following values evaluate to null: 0.
Hope this helps.