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Code Analyzer for C#

There is a newer version: 10.2.0.105762

Why is this an issue?
Calling GetType on a Type variable will always return the System.Type representation, which is equivalent to
typeof(System.Type). This also applies to passing a Type argument to IsInstanceOfType which always returns
false.
In both cases, the results are entirely predictable and should be avoided.
Exceptions
Calling GetType on System.Type is considered compliant to get an instance of System.RuntimeType, as
demonstrated in the following example:
typeof(Type).GetType(); // Can be used by convention to get an instance of 'System.RuntimeType'

How to fix it
Make sure the usage of GetType or IsInstanceOfType is invoked with the correct variable or argument type.
Code examples
Noncompliant code example
void ExamineSystemType(string str)
{
    Type stringType = str.GetType();
    Type runtimeType = stringType.GetType(); // Noncompliant

    if (stringType.IsInstanceOfType(typeof(string))) // Noncompliant; will always return false
    { /* ... */ }
}

Compliant solution
void ExamineSystemType(string str)
{
    Type stringType = str.GetType();

    if (stringType.IsInstanceOfType(str)) // Compliant
    { /* ... */ }
}

Resources
Documentation

   "Type" class 
   "GetType" Method 
   "IsInstanceOfType" Method 

Articles & blog posts

   Difference between "System.Type" and "System.RuntimeType"