web.config file transformations

Question

We release updates to our product several times a year and we need to be able to make changes to customer's web.configs.

We want to be able to apply these changes via c#.

Has anyone used the ctt.exe program and implemented a wrapper class for it? On initial tests it seems to strip all whitespace which isn't ideal.

Answer 1

Found the Microsoft.Web.XmlTransform library which resolves this perfectly without needing 3rd party tools.

using Microsoft.Web.XmlTransform;

...

   using (XmlTransformableDocument document = new XmlTransformableDocument())
                using (XmlTransformation transformation = new XmlTransformation(transformFilePath))
                {
                    document.PreserveWhitespace = true;
                    document.Load(sourceFilePath);

                    var success = transformation.Apply(document);
                    if (!success)
                    {
                        string message = string.Format(
                            "There was an unknown error trying while trying to apply the transform. Source file='{0}',Transform='{1}', Destination='{2}'",
                            sourceFilePath, transformFilePath, destinationFilePath);
                        throw new Exception(message);
                    }

                    document.Save(destinationFilePath);
                }