How to handle error log in framework

This is sample code t开发者_如何学JAVAo catch error in PHP.

<?php
// Error handler function.
function customError($errno, $errstr)
{
    echo "<b>Error:</b> [$errno] $errstr";
}

// Set error handler.
set_error_handler('customError');

// Trigger error.
echo($test);
?> 

I am using frameworks. i dont know how to log errors. I tried by giving function customError($errno, $errstr) in modal and I called from controller it doesn't work for me. How to handle error in frameworks?

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The best approach is to throw exception. Inside your main execution loop catch exceptions and output them into log file.