How to fix the issue when PHP round function cannot be called?

To resolve the issue of not being able to call the round() function in PHP, you can try the following methods:

1. Ensure PHP version compatibility: Make sure you are using PHP version 5 or higher, as the round() function was introduced in PHP 5.
2. Check the spelling of the function name: Make sure you have spelled the name of the round() function correctly, it should be in lowercase letters.
3. Check PHP configuration: Ensure that the relevant function is enabled in the php.ini file. You can search for “disable_functions” in the php.ini file, and if the function is listed there, it may be disabled. If it is disabled, you can try removing or commenting it out in the php.ini file, and then restart your PHP server.
4. Check if the function exists: Use the function_exists() function to check if the round() function exists. You can add the following code in your code to check:

if (function_exists('round')) {
    echo "round函数存在";
} else {
    echo "round函数不存在";
}

If the output result is “round function exists”, it means that the function is available. If the output result is “round function does not exist”, it indicates that the function may not have been correctly installed or configured.

1. Check PHP modules: If you are using PHP extension modules such as Xdebug, it may override or affect the native round() function. Try disabling these extension modules and testing again.

If none of the above methods prove to be effective, it is recommended to check for other possible reasons such as syntax errors in the code or correct permissions. If the issue persists, it is advised to refer to the official PHP documentation, forums, or seek more professional technical support.