Скачать или смотреть Check if a file is exists in a folder using C#

File.Exists sees if a specific file exists.
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There are several ways of testing file existence. File.Exists is the easiest. It is the simplest way of checking that the file exists. It returns true or false.
Bool
True, False
Example. First, the usage of File.Exists is straightforward and should be easy to add to your program. To get its fully qualified name, it is easiest to include the System.IO namespace with a using directive at the top.
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Tip:
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To understand the next example, you have to imagine that the files tested actually exist or don't exist on the hard disk.
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Comparing with FileInfo.
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When you create a new FileInfo with the constructor, it also uses the Path.GetFullPathInternal method and creates a new FileIOPermission object. For this reason, both approaches have similar performance.