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extension

The dot-and-letters ending of a file name, like .cs.

A file extension is the suffix after the last dot in a file name; tools use it to recognize the kind of file (.cs source, .csproj project, .dll assembly).

Examples

  • Program.cs is C# source, Tips.csproj is a project file, and Tips.dll is what the build produces.

See also

source code .csproj file assembly
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