OpenFileDialog Silverlight

Question

I have no problems with using of OpenFileDialog (in Windows Forms). I can not understand for sure where the error using OpenFileDialog in Silverlight( WPF). In my code I am interested by this string , where it necessary to show the path:

var lines = File.ReadLines(fileStream);

all code for Silverlight (does not work):

        private void Button_Click(object sender, RoutedEventArgs e)
    {

        OpenFileDialog opendialog = new OpenFileDialog();
        System.IO.Stream fileStream = opendialog.File.OpenRead();
        if (opendialog.ShowDialog() == true)
        {
            var lines = File.ReadLines(fileStream); 
            string pattern = @"set vrouter ""([\w-]+)""";

            var matches =
                lines.SelectMany(line => Regex.Matches(line, pattern)
                    .Cast<Match>()).Where(m => m.Success)
                    .Select(m => m.Groups[1].Value)
                    .Distinct();

            foreach (String match in matches)
            {

                textBox1.AppendText(match + Environment.NewLine);
            }
        }
    }
}

}

Code for Windows Forms (works well):

        private void button1_Click(object sender, EventArgs e)
    {
        OpenFileDialog opendialog = new OpenFileDialog();
        if (opendialog.ShowDialog() == DialogResult.OK)
        {
            var lines = File.ReadLines(opendialog.FileName);
            string pattern = @"set vrouter ""([\w-]+)""";

                var matches = 
                    lines.SelectMany(line=> Regex.Matches(line, pattern)
                        .Cast<Match>()).Where(m => m.Success)
                        .Select(m => m.Groups[1].Value)
                        .Distinct();

                foreach (String match in matches)
                {

                        textBox1.AppendText(match + Environment.NewLine);
                }
            }



    }

Answer 1

Silverlight runs with elevated permissions by default(simply saying in sandbox), it means

var lines = File.ReadLines(fileStream);

wil not work, for 2 reasons:

1. parameter should be string path, not a stream in silverlight api, at least.
2. File.ReadLines will not work, because it works only for trusted applications.

based on above, your issue can be solved by following code:

OpenFileDialog opendialog = new OpenFileDialog();
if (opendialog.ShowDialog() == true)
{
   string text = string.Empty;
   using (StreamReader reader = opendialog.File.OpenText()) 
   {
   text = reader.ReadToEnd();
   }
   // do stuff here
}

or another options provided by msdn : http://msdn.microsoft.com/en-us/library/cc221415(v=vs.95).aspx

Answer 2

found that I was searching for! this example (with OpenFileDialog Silverlight) works well:

        private void Button_Click(object sender, EventArgs e)
    {
        OpenFileDialog opendialog = new OpenFileDialog();
        opendialog.Multiselect = true;
        bool? dialogResult = opendialog.ShowDialog();
        if (dialogResult.HasValue && dialogResult.Value)
        {
            textBox1.Text = string.Empty;
            foreach (var file in opendialog.Files)
            {
                Stream fileStream = file.OpenRead();
                using (StreamReader reader = new StreamReader(fileStream))
                {

                    string pattern = @"set vrouter ""([\w-]+)""";
                    while (!reader.EndOfStream)
                    {
                        var matches =
                            Regex.Matches(reader.ReadToEnd(), pattern)
                                .Cast<Match>().Where(m => m.Success)
                                .Select(m => m.Groups[1].Value)
                                .Distinct();

                        foreach (var match in matches)
                        {

                            textBox1.Text += val;
                        }