What to do if php empty error occurs

php empty error is because empty only detects variables. Detecting anything that is not a variable will result in a parsing error. The solution is to directly detect the value returned by the function without using empty. The code is such as "$length=strlen ('test');echo empty($length);".

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Solution to error reported by PHP empty function

Solution to the error reported by PHP empty function when detecting a non-variable.

When developing in PHP, when you use empty to check the result returned by a function, an error will be reported:

Fatal error: Can't use function return value in write context

For example The following code:

<?php 
echo empty(strlen(&#39;test&#39;));

Go to the PHP online manual to view. In the description of the empty function, there is the following text:

Note :  empty()  only checks variables as anything else will result in a parse error. In other words, the following will not work: empty(trim($name)).

Conclusion: empty() only detects variables and detects any non- Variables will cause parsing errors!

Therefore, we cannot use empty to directly detect the value returned by the function. The solution to the above example is as follows:

<?php
$length = strlen(&#39;test&#39;);
echo empty($length);

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