CODEWITHSUNDEEP
c#xamarinxamarin.forms
md_hackingawayatcode
md_hackingawayatcode

Reputation: 23

ArgumentException in StreamWriter in Xamarin.Forms

I am writing a Xamarin.Form PLC for Android and iOS, and have a place where I need to write some application stuff to a text file embedded resource. I've implemented reading from the same text file successfully, with same syntax just using StreamReader, but the StreamWriter implementation looks like this:

                Assembly assembly = GetType().GetTypeInfo().Assembly;
                string resource = "jetStream.Results.settings.txt";
                using (Stream stream = assembly.GetManifestResourceStream(resource)) {
                    using (StreamWriter writer = new StreamWriter(stream)) {
                       //do stuff
                    }
                }

StreamWriter is throwing an argument of "Stream is not writeable" at System.IO.StreamWriter. Am I doing something obvsiously wrong? Why is the Stream Readable but not Writeable using the same assembly/resource/stream construction?

Upvotes: 2

Views: 730

Answers (2)

Bill Reiss
Bill Reiss

Reputation: 3460

Depending on what you want to write, if it's just things like application settings, you can use the Application.Properties collection http://www.kymphillpotts.com/exploring-xamarin-forms-1-3-properties-dictionary/ otherwise I agree with Jon's answer.

Upvotes: 1

Jon G Stødle
Jon G Stødle

Reputation: 3904

The stream from GetManifestResourceStream is not writable. The stream's file is embedded in the assembly at build time and cannot be changed. You'll have to write the file to disk before you can write to it.

string resource = "jetStream.Results.settings.txt";
using (Stream stream = assembly.GetManifestResourceStream(resource))
using (var fs = new FileStream(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Personal)), FileMode.Create, FileAccess.Write))
using (var stream = new MemoryStream())
using (var writer = new StreamWriter(fs))
{
    rStream.Stream.CopyTo(stream);
    writer.Write(stream.ToArray());
}

After this you can read and write to the file on disk.

Upvotes: 2

Related Questions