CA1511: Use ArgumentException throw helper

Property	Value
Rule ID	CA1511
Title	Use ArgumentException throw helper
Category	Maintainability
Fix is breaking or non-breaking	Non-Breaking
Enabled by default in .NET 9	As suggestion

Cause

Code checks whether an argument is null or an empty string and then conditionally throws an ArgumentException.

Rule description

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 ArgumentException.ThrowIfNullOrEmpty(String, String) are simpler and more efficient than if blocks that construct a new exception instance.

Example

The following code snippet shows a violation of CA1511:

void M(string arg)
{
    if (string.IsNullOrEmpty(arg))
        throw new ArgumentException("", "arg");
}

The following code snippet shows the fix:

void M(string arg)
{
    ArgumentException.ThrowIfNullOrEmpty(arg);
}

How to fix violations

Replace the if block that throws the exception with a call to ArgumentException.ThrowIfNullOrEmpty(String, String). Or, in Visual Studio, use the lightbulb menu to fix your code automatically.

When to suppress warnings

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.

Suppress a warning

If you just want to suppress a single violation, add preprocessor directives to your source file to disable and then re-enable the rule.

#pragma warning disable CA1511
// The code that's violating the rule is on this line.
#pragma warning restore CA1511

To disable the rule for a file, folder, or project, set its severity to none in the configuration file.

[*.{cs,vb}]
dotnet_diagnostic.CA1511.severity = none

For more information, see How to suppress code analysis warnings.