Visual Studio warning level meanings?

Question

On the build tab in a Web Application project I have a setting called "Warning Level". I can set a value from 0 to 4. What do these values mean? Will a value of 0 be more strict and generate more warnings, or vice versa? I haven't been able to find any documentation on it yet, but perhaps I'm looking in the wrong place.

Answer 1

This link shows you the definitions of the warning levels (I'm assuming you are using C# code in your web project). Level 4 is the most strict.

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• 0: Turns off emission of all warning messages.
• 1: Displays severe warning messages.
• 2: Displays level 1 warnings plus certain, less-severe warnings, such as warnings about hiding class members.
• 3: Displays level 2 warnings plus certain, less-severe warnings, such as warnings about expressions that always evaluate to true or false.
• 4: Displays all level 3 warnings plus informational warnings. This is the default warning level at the command line.
• 5: Displays level 4 warnings plus additional warnings from the compiler shipped with C# 9.0.

Anything greater than 5 is treated as 5.