C# .NET - moving files from one folder to another

i have these lines of code which transfers files from one folder to another. but an error occurs when the file to transfer is being used by another process... 


[CODE]
private int MoveFiles(String sourcePath, String destinationPath)
		{ 
			int fileCounter = 0; 

			if (destinationPath.LastIndexOf("\\") != destinationPath.Length - 1) 
			{ 
				destinationPath += "\\"; 
			} 

			foreach (string sFile in Directory.GetFiles(sourcePath)) 
			{ 
				string extension = sFile.Substring(sFile.LastIndexOf(".")); 

				if (extension == ".xml" || extension == ".XML") 
				{ 
					if (File.Exists(string.Concat(destinationPath, Path.GetFileName(sFile)))) 
					{ 
						if (MessageBox.Show(String.Format("{0}: already exists. Replace?", string.Concat(destinationPath, Path.GetFileName(sFile))), "TODO", MessageBoxButtons.YesNo, MessageBoxIcon.Information) == DialogResult.Yes) 
						{ 
							File.Delete(string.Concat(destinationPath, Path.GetFileName(sFile))); 
							File.Move(sFile, string.Concat(destinationPath, Path.GetFileName(sFile))); 
							++fileCounter; 
						} 
					} 
					else 
					{ 
						File.Move(sFile, string.Concat(destinationPath, Path.GetFileName(sFile))); 
						++fileCounter; 
					} 
				} 
			} 
			return fileCounter; 
		} 

[/CODE]



the error will occur in this line
[CODE]

						File.Move(sFile, string.Concat(destinationPath, Path.GetFileName(sFile))); 
[/CODE]

how will i check if the file is being used by another process before i'll transfer it? thanks

You should use Try Catch block to know the problem exactly.

Some times problem occurs when the handle to file is not kept.

By the way insert this code 

[CODE]
using (FileStream fs = File.Create(path)) {}
[/CODE]
just after this line

[CODE]
if (File.Exists(string.Concat(destinationPath, Path.GetFileName(sFile))))      	
{
....
.....
...
[/CODE]
and check whether problem persists.

the code is quite confusing...
which path am i going to place inside the parentheses? the destination path? or the sourcepath? what is the effect of using these lines?

place your source path inside the parentheses.

this statement just creates a file stream around the file and closes it explicitely.

You will have to make to it read ony before moving the file or 
Handle System.IO.IOException Exception in try catch block and massage to user accordingly .
You can't move file when its open in writable mode.

i already tried the try catch method.. and it worked fine
but what i really like to do is to check if it is used by another process or not rather than a try catch block.. any other idea? still got a problem with it... thanks

As far as I know, that's the only way for you to determine if the file is being used or not.  In your try/catch block, you can check for the error code or error message and if it says file is being used, then the file is being used.