Question

I have code that calls the ReadXml method of the DataSet class and passes in a file name ReadXml(strFileName). Occasionally this throws a System.IO.IOException because the file is being used by another process.

If I change the code to use the ReadXml(stream) method and pass in a FileStream like this:

using(FileStream fs = new FileStream(this.filename, FileMode.Open, FileAccess.Read, FileShare.ReadWrite ))
{
     MyDS.ReadXxml(FileStream);
}

Will that prevent the IOException from occuring? What is going on under the hood when you simply pass in a file name?

Answer 1

The DataSet class will create a FileStream object for you if you pass in the filename as a string. The overloaded method that takes a Stream as a parameter allows you to pass in a Stream object if you have one instead of a filename.

The version that takes a string as a parameter will simply create a FileStream and pass that onto the version that takes a Stream as a parameter.

You should use the overload that suits the data you have. In this case the string.