CodeXchange: User Contributed Snippets

C# : Return Information from the Call Stack to help in Debugging your Code

Damon Carr — Mon, 02 May 2005 18:08:52 GMT

		public string CallingMethod
		{
			get
			{
				StackFrame sf;
				StackTrace st = new StackTrace(true);
				StringBuilder oString = new StringBuilder();
				for(int i =1; i< st.FrameCount; i++ )
				{
					// Note that high up the call stack, there is only
					// one stack frame.
					sf = st.GetFrame(i);
					oString.Append("METHOD: " + sf.GetMethod());
					oString.Append(" Line Number: " + sf.GetFileLineNumber() + AppUtils.StringSeperator);
					
				}
				return oString.ToString();
			}
		}

C#: Code to Detect if a System is Shutting Down and will Exit with the Exit Code You Provide

Damon Carr — Sun, 24 Apr 2005 02:21:46 GMT

			int exitcode = 0;
			const int END_CODE_SHUTTINGDOWN = 1024;
			try
			{
				String[] args = Environment.GetCommandLineArgs();
				// The first parameter on the command line would be the exit code you wanted the
				// process to return to the system
				if (args.Length > 1)
					exitcode = int.Parse(args[1]);
				else
					exitcode = END_CODE_SHUTTINGDOWN;
			}
			catch (Exception ex)
			{
				exitcode = ex.GetHashCode();
			}
			if (Environment.HasShutdownStarted)
				Environment.Exit(exitcode);

C#: Test for Out Of Memory using Unsafe Code

Damon Carr — Mon, 02 May 2005 18:53:34 GMT

using System;
using System.Runtime.InteropServices;
public unsafe class Memory
{
	// Heap API flags
	const int HEAP_ZERO_MEMORY = 0x00000008;
	static int ph = GetProcessHeap();
    
	public static void* Alloc(int size) 
	{
		void* result = HeapAlloc(ph, HEAP_ZERO_MEMORY, size);
		if (result == null) 
			throw new OutOfMemoryException();
		return result;
	}
}

C#: Function to Find any Type by name by searching through all the refernced assemblied in your application and returning a .NET Type from the passed in (namespace qualified) string

Damon Carr — Sun, 24 Apr 2005 04:15:32 GMT

		public Type FindTypeTypeFromStringName(String TypeName)
		{	
			/*************************************************************
			 * Damon W. Carr, CEO agilfactor
			 * 
			 * This code will find a Give Type using its String Name 
			 * across ALL ASSEMBLIES you have referenced and return the 
			 * Type of the item which is far more useful then just the 
			 * String name. If you only have one assembly you will not need
			 * this.
			 * 
			 * Discussion (?)
			 *			
			 *			Add an overload to allow the searching for both types
			 *			AND the assembly they are in when you know the type
			 *			you want AND the assembly and there are two types with		
			 *			the same name. 
			 * 
			 *			However if you know that much, you
			 *			really wouldn't need this function as you would just 
			 *			check the types in THAT assembly using reflection 
			 *			directly . You would not need this routine if you 
			 *			knew the Type's name and the assembly in other words.
			 * 
			 * CAVEATS:	Be aware, if you are looking for a Type and there
			 *			are more then one match, only the first one will be 
			 *			returned.
			 * ***********************************************************/
            		
			Assembly oEntryAssembly = Assembly.GetCallingAssembly();
			Type oMatchedType = null;
			AssemblyName[] ReferencedAssemblies = oEntryAssembly.GetReferencedAssemblies();
			Assembly oCurrentAssembly;
                        
			oMatchedType = oEntryAssembly.GetType(TypeName);
			if (oMatchedType == null) 
			{
				foreach(AssemblyName oName in ReferencedAssemblies)
				{
					/***********************************************************
					 * Assemblies are cached. This is not slow so don't worry
					 * about performance. This will perform very well
					 * *******************************************************/
					oCurrentAssembly = Assembly.Load(oName); //Load the assembly from the AssemblyName type
					oMatchedType = oCurrentAssembly.GetType(TypeName);
					if (oMatchedType != null)
					{
						//You Found the Type you Wanted
						break;
					}
					
				}
			}
			return oMatchedType;
       }

C# : Checks a String for null or Empty and returns a bool. This is a static so you invoke it from the class. There are no threading issues as String are immutable and the nature of the Thread Call Stack

Damon Carr — Sun, 24 Apr 2005 15:50:45 GMT

C# : Checks a String for null or Empty and returns a bool. This is a static so you invoke it from the class. There are no threading issues as String are immutable and the nature of the Thread Call Stack [C#]

C# : Great Debug Information using the StackFrame

Damon Carr — Wed, 04 May 2005 16:26:55 GMT

		public string CallingMethod
		{
			get
			{
				StackFrame sf;
				StackTrace st = new StackTrace(true);
				StringBuilder oString = new StringBuilder();
				for (int i = 1 ; i < st.FrameCount ; i++)
				{
					// Note that high up the call stack, there is only
					// one stack frame.
					sf = st.GetFrame(i);
					oString.Append("METHOD: " + sf.GetMethod());
					oString.Append(" Line Number: " + sf.GetFileLineNumber() + AppUtils.StringSeperator);
				}
				return oString.ToString();
			}
		}

C# : A Best Practice Use of the ReaderWriterLock for Multithreaded Environments

Damon Carr — Thu, 28 Apr 2005 15:02:52 GMT

	public static String GetApplicationName()
		{	
			// This is mostly here as a tutorial on using the Reader Writer Lock;
			const int CONST_WAIT_TIME_TO_AQUIRE = 1000;
            
			ReaderWriterLock oRWLock;
			
			if (AppUtils.StringEmpty(AppName)) {
				oRWLock = new ReaderWriterLock();
                
				try {
					oRWLock.AcquireReaderLock(CONST_WAIT_TIME_TO_AQUIRE);
				
					if (oRWLock.IsReaderLockHeld)
					{
						// Check again to possibly avoid the upgrade
						if (AppUtils.StringEmpty(AppName)) 
						{
							oRWLock.UpgradeToWriterLock(CONST_WAIT_TIME_TO_AQUIRE);
							
							if (oRWLock.IsWriterLockHeld) 
								AppName = ConfigurationSettings.AppSettings.Get("ApplicationName").ToString();
							else
								throw new Exception("Unable to get Writer Lock on AppName");
						}
					}	
					else
						throw new Exception("Unable to aquire Reader Lock");
				} 
				finally 
				{	
					oRWLock.ReleaseLock();
				}
			}
		
			return AppName;
		}

C# : Proper Way to code a Factory as static in an Abstract Class (NOTE: Look for the StringEmpty Static to compile this)

Damon Carr — Sun, 24 Apr 2005 15:48:08 GMT

		public static Car GetCar(String CarType)
		{
			// NOTE: See the reference code for the static StringEmpty function
			// also uploaded. You are ThreadSafe because Strings are immutable and 
			// you have no risk of concurrent access or corruption as each thread has a dedicated 
			// parameter stack
			if (AppUtils.StringEmpty(CarType))
				throw new Exception("You must pass in a value to the GetCar factory. You passed in an empty string or null");
			object oCar = Activator.CreateInstance(Type.GetType(CarType));
			Car oCastCar = oCar as Car;
			if (oCastCar != null)
				return oCastCar;
			else
				throw new Exception("Invalid Cast. Type Requested does not implement the required interface");
		}