CRR0016 - Method call's return value is ignored

• Feb 28, 2025

This analyzer detects calls to non-void methods where the return value is not considered. Normally, if a method returns data, you should check or save the output. Consider the following example.

• C#
• VB.NET

string s = "(10.2, 381.8)";
s.Replace(",", ";"); // CRR0016

Dim s As String = "(10.2, 381.8)"
s.Replace(",", ";") ' CRR0016

In this code, the programmer expects that the Replace method modifies the source string. Since it is not so, the statement is useless and should be changed as follows.

• C#
• VB.NET

string s = "(10.2, 381.8)";
s = s.Replace(",", ";");

Dim s As String = "(10.2, 381.8)"
s = s.Replace(",", ";")

See Also

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