eXclusiveMinds » Reflection

Reflection Examples in C#

eXclusiveMinds — Fri, 13 Mar 2009 00:06:14 +0000

Following example demonstrate about loading assembly dynamically, creating instance, invoking method and getting/setting property value.

Creating instance from assembly (in project References)
Following example creates objects of DateTime class (this is from system assembly).

DateTime dt = (DateTime)Activator.CreateInstance(typeof(DateTime));
DateTime dt = (DateTime)Activator.CreateInstance(typeof(DateTime),
                                                       new object[] { 2009, 10, 9 });

Creating instance (with dynamically loaded assembly)
sample MyCalculator class

namespace MyCalc
{
    public class MyCalculator
    {
        public MyCalculator() {}
        public double Number { get;set;}
        public void Clear() {}
        private void DoClear() {}
        public double Add(double number) {}
        public static double Pi {}
        public static double GetPi() {}
    }
}

Various example or using reflection with MyCalc.dll assembly
Loading assembly from MyCalc.dll dynamically

Assembly myAssembly = Assembly.LoadFile(@"c:\MyCalc.dll");

Getting type of MyCalculator class

Type type = myAssembly.GetType("MyCalc.MyCalculator");

Creating instance of MyCalculator

object myCalcInstance = Activator.CreateInstance(type);

Getting property info

PropertyInfo myPropertyInfo = type.GetProperty("Number");

Getting property value

double value = (double)myPropertyInfo.GetValue(myCalcInstance, null);

Setting property value

myPropertyInfo.SetValue(myCalcInstance, 10.0, null);

Getting static property info

PropertyInfo piPropertyInfo = type.GetProperty("Pi");

Getting value from static property

double piValue = (double)piPropertyInfo.GetValue(null, null);

Invoking public instance method

type.InvokeMember("Clear",
    BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.Public,
    null, myCalcInstance, null);

Invoking private instance method

type.InvokeMember("DoClear",
    BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.NonPublic,
    null, myCalcInstance, null);

Another public instance method

double value = (double)type.InvokeMember("Add",
    BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.Public,
    null, myCalcInstance, new object[] { 20.0 });

Invoking public static method

double piValue = (double)type.InvokeMember("GetPi",
    BindingFlags.InvokeMethod | BindingFlags.Static | BindingFlags.Public,
    null, null, null);

Get Method Names using Reflection in C#

eXclusiveMinds — Tue, 27 Jan 2009 00:11:00 +0000

By using Type.GetMethods we can get method names for given type using C#; which returns collection of MethodInfoobjects.

To filter returned methods This BindingFlags is used for filtering returned method.

Example: Getting names of static methods

using System.Reflection;
MethodInfo[] methodInfoList = typeof(MyClass).GetMethods(BindingFlags.Public |
                                                      BindingFlags.Static);
 
// sorting methods by it name
Array.Sort(methodInfoList,
        delegate(MethodInfo methodInfo1, MethodInfo myMethodInfo2)
        { return methodInfo1.Name.CompareTo(myMethodInfo2.Name); });
 
// Displaying method name
foreach (MethodInfo myMethodInfo in methodInfoList)
{
  Console.WriteLine(myMethodInfo.Name);
}

Get Property Names using Reflection in C#

eXclusiveMinds — Sun, 14 Dec 2008 00:12:47 +0000

This example shows how we can get names of all properties for a specific type by using Type.GetProperties.

Example

 
PropertyInfo[] propertyInfoCollection;
propertyInfoCollection = typeof(MyTestClass).GetProperties(BindingFlags.Public |
                                              BindingFlags.Static);
// sorting property
Array.Sort(propertyInfoCollection,
        delegate(PropertyInfo myPropertyInfo1, PropertyInfo myPropertyInfo2)
        { return myPropertyInfo1.Name.CompareTo(myPropertyInfo2.Name); });
 
// Displaying property names by iterating through collection
foreach (PropertyInfo property in propertyInfoCollection)
{
  Console.WriteLine(property.Name);
}

Get Calling Method using Reflection in C#

eXclusiveMinds — Tue, 02 Dec 2008 00:15:00 +0000

To get name of the calling method we use method StackTrace.GetFrame.
Example showing how we can get name of calling method.

using System.Diagnostics; StackTrace stTrace = new StackTrace(); Console.WriteLine(stTrace.GetFrame(1).GetMethod().Name);

Get Call Stack in C#

eXclusiveMinds — Sun, 09 Nov 2008 00:17:02 +0000

Following example shows how we can get call stack with C#.
StackTrace class represents Call Stack.
StackFrame class represents method call.

Example to print call stack method names

using System.Diagnostics; [STAThread] static void Main() { StackTrace stTrace = new StackTrace(); StackFrame[] stackFrames = stTrace.GetFrames(); foreach (StackFrame frame in stackFrames) { Console.WriteLine(stTrace.GetMethod().Name); } }

OUTPUT:

Main nExecuteAssembly ExecuteAssembly RunUsersAssembly ThreadStart_Context Run ThreadStart