Use ArgumentNullException throw helper
Use ArgumentNullException throw helper
Microsoft docsDescription
Argument checks have a substantial impact on code size and often dominate the code for small functions and property setters. These checks prevent inlining and cause substantial instruction-cache pollution. Throw-helper methods such as System.ArgumentNullException.ThrowIfNull are simpler and more efficient than if blocks that construct a new exception instance.
Cause
Code checks whether an argument is null and then conditionally throws an System.ArgumentNullException.
How to fix violations
Replace the if block that throws the exception with a call to System.ArgumentNullException.ThrowIfNull. Or, in Visual Studio, use the lightbulb menu to fix your code automatically.
Example
void M(string arg)
{
if (arg is null)
throw new ArgumentNullException(nameof(arg));
}
void M(string arg)
{
ArgumentNullException.ThrowIfNull(arg);
}When to suppress
It's safe to suppress a violation of this rule if you're not concerned about the maintainability of your code. It is also fine to suppress violations that are identified to be false positives.