Add the possibility to specify an output filename

[SierraNL]

It would be handy to specify the output filename, currently it's only possible to select the output folder. (I guess since you can have more then 1 file). But when you do have one file, it would be great if you could specify it.

This is meant for the console version and the dotnettool version.

[mganss]

Currently, the file names are identical to the C# namespace names (plus ".cs"). So one way of specifying the file name is to set the C# namespace name. It would be a nice feature to be able to specify the file name independently of the namespace. This could be added to the -n option, e.g.

-n XmlNamespace|a.xsd=CSNamespace|Filename.cs

[rashan]

I was badly in need of this feature, so implemented my own File writer to achieve it.

public class SingleFileOutputWriter : FileOutputWriter
    {
        public SingleFileOutputWriter(string directory, bool createIfNotExists = true)
         : base(directory, createIfNotExists)
        {
        }

        public string OutputFile { get; set; }

        public override void Write(CodeNamespace cn)
        {
            var cu = new CodeCompileUnit();
            cu.Namespaces.Add(cn);

            if (string.IsNullOrWhiteSpace(OutputFile))
            {
                OutputFile = $"{cn.Name}.cs";
            }

            WriteFile(Path.Combine(OutputDirectory, OutputFile), cu);
        }
    }

[StefH]

@rashan ; Can you maybe create a PR for this?