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    <p>One problem with your question is that you didn't specify the desired semantics. There are two possible interpretations, and which solution is better, depends on that choice. I assume being unable to load the fallback, is a fatal error.</p> <ol> <li>If the first file does exist, load it, else load the second. If the first file exists, but could not be loaded, show an error.</li> <li>If the first file cannot be loaded, fallback to the second.</li> </ol> <p>If you want the semantics of 1) your first code is fine.</p> <p>If you want the semantics of 2), neither is good. The first code doesn't have these semantics because:</p> <ol> <li>It has a race condition. If the image gets deleted between checking the existence of the file and loading it, it'll fail.</li> <li>If the file exists, but cannot be loaded, an exception will be thrown. This can happen if the file is no valid image, or cannot be opened.</li> </ol> <p>The second one uses exceptions for a common case, which is bad.</p> <p>So to achieve the second semantics I'd use:</p> <pre><code>procedure LoadImage(img: TImage; filename: string); var success:boolean; begin success := false; if FileExists(filename) then try img.Picture.LoadFromFile(filename); success := true; except end if not success then img.Picture.LoadFromFile('default.jpg'); end; </code></pre> <p>Checking for existence before opening makes the error case faster, but the success case slower. So which one is faster depends on your usage.</p> <p>Personally I'd use the third variant over the second, even if the image is only missing occasionally, since I believe a normally operating application should not throw exceptions. I'd only care about the performance issue if benchmarking revealed it to be noticeable.</p> <p>You should also consider a more targeted exception clause. Blanket catching all exception is bad style. Unfortunately I couldn't find a clear specification which exceptions are thrown by <code>TPicture.LoadFromFile</code>, so I'll leave in the blanket clause for now.</p>
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    1. POIs it faster to check a file's existence prior to loading, or to catch the exception when it doesn't exist?
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    1. USCodesInChaos
    1. USCodesInChaos
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    1. CONow if file does not exists procedure will do nothing. So its not the best tip
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      1. USJarek Bielicki
    2. COright, stupid mistake on my part.
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      1. USCodesInChaos
    3. CONow you first load from filename, and then ditch that to load default.jpg. Missing `else`.
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