JJ.Framework.Reflection 1.5.6877.41324

JJ.Framework.Reflection

Extensions to the System.Reflection and System.Linq.Expressions namespaces.

ExpressionHelper

Converts many types of lambda expressions into text or retrieves its resulting value. Here are some of the things it can do:

For instance:

ExpressionHelper.GetText(() => myParam.MyProperty.MyList[i].MySomething)

Will return the string:

"myParam.MyProperty.MyList[i].MySomething"

Similarly you can retrieve its value:

ExpressionHelper.GetValue(() => myParam.MyProperty.MyList[i].MySomething)

which can return:

3

It can also give you method info, parameter names and parameter value info from lambda expressions.

For instance:

ExpressionHelper.GetMethodCallInfo(() => MyMethod(3));

Will return:

MethodCallInfo
{
	Name = "MyMethod",
	Parameters = 
	{
		ParameterType = typeof(int),
		Name = "myParameter",
		Value = 3
	}
};

Accessor

Allows easy access to the internal, private or protected elements of an assembly or class.

For instance if you have the following private method in a class:

class MyClass
{
    private int MyPrivateMethod(int myParameter)
    {
        return 3;
    }
}

You can run that private method, that would otherwise not be available:

var myObject = new MyClass();
var accessor = new MyAccessor(myObject);
int myInt = accessor.MyPrivateMethod(1);

You can do that by writing the following wrapper class:

class MyAccessor
{
    Accessor _accessor;

    public MyAccessor(MyClass myObject) => _accessor = new Accessor(myObject);

    public int MyPrivateMethod(int myParameter) 
		=> _accessor.InvokeMethod(() => MyPrivateMethod(default), myParameter);
}

ReflectionCache

Makes using reflection much faster in certain cases. For instance the GetProperties method can be expensive, which is much faster through the ReflectionCache class.

Example:

private static readonly ReflectionCache _reflectionCache 
	= new ReflectionCache(BindingFlags.Public | BindingFlags.Instance);

PropertyInfo[] properties = _reflectionCache.GetProperties(typeof(MyClass));

You can also get other types of constructs in a fast way:

• GetFields
• GetConstructor
• GetTypeByShortName

ReflectionExtensions

Various helper methods, but one of the most useful features is the GetImplementation method and variations thereof, which allow you to retrieve implementations of a specified base class or interface from an assembly, which is useful for plug-in development.

• GetBaseClasses
  • Returns a type's base type and its base type, etc.
• GetItemType
  • Gets the item type of a collection type.
• GetImplementations
  • Allows you to retrieve implementations of a specified base class or interface from an assembly, which is useful for plug-in development.
• GetPropertyOrException
  • Type.GetProperty returns null if the property does not exist. This method is a little safer than that and throws a clear exception if the property does not exist.
• GetUnderlyingNullableTypeFast
  • Slightly faster than Nullable.GetUnderlyingType.
• GetValue
  • Similar to PropertyInfo.GetValue, but for static properties you can now omit the object parameter.
• IsAssignableFrom / IsAssignableTo
  • Similar to the original Type.IsAssignableFrom, but now also an IsAssignableTo variation, if you find that more intuitive. Also has variations with a type argument e.g. myInterfaceType.IsAssignableFrom<MyClass>();
• IsIndexer
  • Can tell you if a MethodBase points to an indexer property.
• IsNullableType
  • Can tell you if a Type is a nullable type.
• IsProperty
  • Can tell you if a MethodBase is a property.
• IsReferenceType
  • Can tell you if a Type is a reference type.
• IsStatic
  • Can tell you if a MemberInfo is static.
• IsSimpleType
  • Tells you if a Type is a 'simple type'. A simple type can be a .NET primitive types: Boolean, Char, Byte, IntPtr, UIntPtr, the numeric types, their signed and unsigned variations, but also String, Guid, DateTime, TimeSpan and Enum types.

ReflectionHelper

• CreateInstance
  • A variation on the existing Type.CreateInstance, that takes a type name as a string, instead of a Type.
• IsDefault
  • Can tell you if a value is the default value for its type. (E.g. 0 is the default value for Int32.)
• IsSimpleType
  • Tells you if a value is of a 'simple type'. A simple type can be a .NET primitive types: Boolean, Char, Byte, IntPtr, UIntPtr, the numeric types, their signed and unsigned variations, but also String, Guid, DateTime, TimeSpan and Enum types.
• TypesFromObjects
  • You can pass objects to it, and it will return the concrete types of those objects, with some tolerance for nulls.