Heya, Frank.
The main advantage to using try/catch is that you can catch Exceptions *anywhere*.
For example (and using the doQuery() function above):
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function runABadQuery()
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{
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doQuery( 'this is not valid SQL' );
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}
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ob_start();
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try
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{
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echo 'You will never see this.';
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runABadQuery();
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echo 'You will never see this, either.';
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}
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catch( Exception $e )
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{
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// Alert admin
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mail
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(
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'my@email.address',
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'Exception thrown: ' . date('F j, Y g:i:s a'),
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$e->getMessage()
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);
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// Clear the output buffer.
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while( ob_end_clean() )
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{
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}
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// Output an error message.
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echo 'The server made a boo-boo. This should be your customized 500 error page. You could even use include() here if you wanted.';
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// We're done here.
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exit;
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}
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ob_end_flush();
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Notice that even though the Exception gets thrown way down the stack in doQuery() [called by runABadQuery() called by main()], the Exception still gets caught.
In the code above, you can enclose the entirety of your code within a try/catch block, and if an Exception gets thrown *anywhere*, your code will stop, it will send an email with the text of the Exception to an administrator, and it will display a generic error page.
Note also that by using output buffering, you can prevent any output from reaching the browser until the script has successfully finished executing.
