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C# and GDAL implementation - Dataset not returning a value

I am trying to automate a simple geotiff to KMZ process using GDAL and C#
The code I have written is a little buggy and I am having a lot of trouble working out how to use the API. I am hoping this is a simple fix for more advanced developers.
My code is as follows:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OSGeo.GDAL;
namespace TestingTIFFtoKMZ
{
class Program
{
static void Main(string[] args)
{
string outputName = Environment.CurrentDirectory + #"\BR01899_Mackenzie_09_EXPORT";
string vrtfile = outputName + #"\tempMosaic.vrt";
string filenameKMZ = outputName + #"\" + Environment.CurrentDirectory + ".kmz";
string[] tiffFiles = Directory.GetFiles(outputName, "*.tif");
var vrtOptions = new GDALBuildVRTOptions(new[] { "-overwrite" });
GDALTranslateOptions transOptions = new GDALTranslateOptions(new[] { "-of", "KMLSUPEROVERLAY", "-co", "format=png" });
Dataset vrtDataset = Gdal.wrapper_GDALBuildVRT_names(vrtfile, tiffFiles, vrtOptions, null, null);
// vrtDataset.Dispose();
Gdal.wrapper_GDALTranslate(filenameKMZ, vrtDataset, transOptions, null, null);
}
}
}
I am getting a null return value on the vrtDataset variable and (i think) as a result, I am getting a null reference error when I call the Gdal.wrapperGDALTranslate method.
Any help appreciated. Thanks.

It needed,
Gdal.AllRegister();
and an absolute path to the VRT file being created.

XmlReader testing of string returned for newline

I am writing a C# class to use for generating email lists to use when a process either succeeds or fails. In running through XmlReader examples from the web, I found that validating the Read() is tougher than it looks.
I can use string.IsNullOrEmpty(x) to test for a null value or and empty node, but it will still blow by that test showing a "\n " in the tooltip for x. Testing for "\n ", '\n ', '\n'. "\n" or char(13) all fail. If I use x.Contains((char)13), it always find it and goes into the code trying to build the email address list. So far, it either always fails or always succeeds.
I found some old posts on stackoverflow where it seemed like the question was the same, but my results don't match with the answers. My environment is Windows 8.1 running Visual Studio 2013 with .Net Framework 4.51. The example from the web I was trying to make work before using the solution in my class is at Microsoft.com
My conversion is below:
using System;
using System.Text;
using System.Linq;
using System.Xml;
using System.Xml.Schema;
using System.IO;
using System.Collections.Generic;
namespace XMLDemo
{
public class project
{
public static void Main()
{
string uri = #"C:\\events\items.xml";
string process_state = "Item";
string emails = StreamEmailAddress(uri, process_state);
}
private static string StreamEmailAddress(string uri, string process_state)
{
XmlReaderSettings settings = new XmlReaderSettings();
settings.DtdProcessing = DtdProcessing.Parse;
XmlReader reader = XmlReader.Create(uri, settings);
string returnValue = "";
reader.MoveToContent();
while (reader.Read())
{
string x = reader.Value;
if ((string.IsNullOrEmpty(x) == false) && (x.Contains((char)13)))
{
returnValue = returnValue + x + "; ";
}
}
Console.WriteLine("Made it to the end: " + returnValue);
return returnValue;
}
}
}

You should use string.IsNullOrWhiteSpace

SOLVED: After futzing with it all day, I looked at it with slightly fresher eyes after posting and saw the blatant error. I was using the incorrect function and trying to resolve line feeds by myself. By replacing IsNullOrEmpty(x) with IsNullOrWhiteSpace(x), I got the string of data as expected. Doing the code with email addresses will be easy now.

Does not contain definition after reference has been added

I am VERY new to C# so it is possible this is a really easy problem, but even after all my reading I cant find a way to add the definitions Visual Studio 2010 wants despite having added the using statements and the references on the MSDN docs page for each expression.
My Error:
System.windows.forms does not contain a definition for document
I added the reference "presentationframework" based on something I was reading on the Microsoft site. Thanks to some of the comments below I discovered I was apparently mixing two different ways to get text from the box. All I need to be able to do is paste content into the textbox, and get the contents of the box when i press a button. Can someone tell (or better yet show) me definitively how to do this without mixing strategies?
Form1.cs:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows.Documents;
using System.Windows.Controls.RichTextBox;
using System.Windows.Forms;
using System.Windows.Controls;
using System.Collections;
namespace WindowsFormsApplication1
{
public partial class HackController : Form
{
ArrayList ipList = new ArrayList();
ArrayList acctList = new ArrayList();
int myAcct = 0;
string myIp = "";
public HackController()
{
InitializeComponent();
}
public void sync_Click(object sender, EventArgs e)
{
string data = new TextRange(rtb.Document.ContentStart, rtb.Document.ContentEnd).Text;// ERROR HERE
string[] lines = Regex.Split(data, "\n");
Regex ipMatch = new Regex(#"\d+.\d+.\d+.\d+");
Regex acctMatch = new Regex(#"#\d+");
foreach(string line in lines)
{
foreach(Match m in ipMatch.Matches(line))
{
ipList.Add(m);
}
foreach( Match m in acctMatch.Matches(line))
{
acctList.Add(m);
}
}
}
}
}

Here's a (rather strange) sample showing one way to display data in a WinForms RichTextBox control. (Sorry, but it's the only sample I can find in my programming because I'm usually using Developer Express WinForms controls instead of the basic .Net ones.)
But first, to be 100% sure you are not mixing WinForms and WPF, make sure that when you create the project you select WinForms as the project template type (not WPF). And when you drag-and-drop the RichTextBox control from the Visual Studio toolbox onto your form, make sure it is the WinForms RichTextBox, not the WPF one.
You can check this by looking in the .Designer.cs file, and find the definition of the RTB control created by the Visual Studio designer. It should look something like this:
this.rtbResults = new System.Windows.Forms.RichTextBox();
...
...
//
// rtbResults
//
this.rtbResults.BorderStyle = System.Windows.Forms.BorderStyle.None;
this.rtbResults.Location = new System.Drawing.Point(12, 52);
this.rtbResults.Name = "rtbResults";
this.rtbResults.Size = new System.Drawing.Size(640, 133);
this.rtbResults.TabIndex = 17;
this.rtbResults.Text = "";
...
...
private System.Windows.Forms.RichTextBox rtbResults;
The important thing being that it says "System.Windows.Forms.RichTextBox", not something else.
OK, here's my strange example, which displays the results of a Scrabble cheater program:
/// <summary>
/// Method to display the results in the RichTextBox, prefixed with "Results: " and with the
/// letters J, Q, X and Z underlined.
/// </summary>
private void DisplayResults(string resultString)
{
resultString = UnderlineSubString(resultString, "J");
resultString = UnderlineSubString(resultString, "Q");
resultString = UnderlineSubString(resultString, "X");
resultString = UnderlineSubString(resultString, "Z");
rtbResults.Rtf = #"{\rtf1\ansi " + "Results: " + resultString + "}";
}
/// <summary>
/// Method to apply RTF-style formatting to make all occurrences of a substring in a string
/// underlined.
/// </summary>
private static string UnderlineSubString(string theString, string subString)
{
return theString.Replace(subString, #"\ul " + subString + #"\ul0 ");
}
This uses Microsoft's proprietary Rich Text Format, but RichTextBox can also use straight text. And this demo only writes to the RTB, it doesn't read from it, although doing that is fairly trivial.
Hope this helps.

Windows 7 clipboard copy paste operation using C#

I'm working on a Windows application where I need to use clipboard data. I am trying to copy text from clipboard by the code below.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Threading;
namespace MultiValuedClipBoard
{
class Class1
{
public String SwapClipboardHtmlText(String replacementHtmlText)
{
String returnHtmlText = "hello";
if (Clipboard.ContainsText(TextDataFormat.Html))
{
returnHtmlText = Clipboard.GetText(TextDataFormat.Html);
Clipboard.SetText(replacementHtmlText, TextDataFormat.Html);
}
return returnHtmlText;
}
}
}
Calling the above function by:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Media;
namespace MultiValuedClipBoard
{
class Program
{
static void Main(string[] args)
{
Class1 aas = new Class1();
string a = aas.SwapClipboardHtmlText("chetan");
Console.WriteLine(a);
Console.ReadLine();
}
}
}
When running this code it gives the output "Hello" which is the default value, not clipboard data.

Your code will not work because of two reasons:
[1] When you say:
if (Clipboard.ContainsText(TextDataFormat.Html))
Here you are basically assuming that the clipboard already contains a text and that too in HTML format, but depending on the values you are setting in the clipboard it doesn't look like you are intending to use the pre-existing clipboard value anywhere in your program. So, this if condition should not be there.
[2] Secondly, you are further trying to set the string "chetan" to the clipboard which is definitely not in HTML format. So,
Clipboard.SetText(replacementHtmlText, TextDataFormat.Html);
becomes
Clipboard.SetText(replacementHtmlText, TextDataFormat.Text);
Hence, effectively, your new code becomes something like this:
String returnHtmlText = "hello";
//if (Clipboard.ContainsText(TextDataFormat.Html))
//{
returnHtmlText = Clipboard.GetText(TextDataFormat.Text);
Clipboard.SetText(replacementHtmlText, TextDataFormat.Text);
//}
return returnHtmlText;

Clearly Clipboard.ContainsText(TextDataFormat.Html) evaluates to false. Which means that the clipboard in fact does not contain text in the format you specify.
I changed your program to prove the point:
[STAThread]
static void Main(string[] args)
{
Clipboard.SetText("boo yah!", TextDataFormat.Html);
Class1 aas = new Class1();
string a = aas.SwapClipboardHtmlText("chetan");
Console.WriteLine(a);
Console.WriteLine(Clipboard.GetText(TextDataFormat.Html));
Console.ReadLine();
}
Output:
boo yah!
chetan

Download link encryption with XOR

Can I maybe get some help with this? As I am very confused. I copy-pasted an XOR encryption class, and I XOR encrypted the download link to my Minecraft Mod Installer .exe hosted on my website. However when I wrote the following code I always got an error because the text input isn't a proper Uri. Is there a way I can make this work?
SSCCE below
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using System.IO;
using System.Net;
private void startButton_Click(object sender, EventArgs e)
{
startButton.Enabled = false;
WebClient client = new WebClient();
client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(client_DownloadProgressChanged);
client.DownloadDataCompleted += new DownloadDataCompletedEventHandler(client_DownloadDataCompleted);
client.DownloadDataAsync(new Uri(EncryptorDecryptor.EncryptDecrypt("8a33b8a537d4e17ec4ac7041df43d892821c16dc15cf84fb33a672ab76c72119126f9c4849cf55423b0112c4b4")), Path.GetTempPath() + "mcmodinstaller.exe");
}
void client_DownloadDataCompleted(object sender, DownloadDataCompletedEventArgs e)
{
MessageBox.Show("Successful!",
"Download",
MessageBoxButtons.OK,
MessageBoxIcon.Information);
Process.Start(Path.GetTempPath() + "mcmodinstaller.exe");
startButton.Enabled = true;
}
void client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
{
downloadBar.Maximum = (int)e.TotalBytesToReceive / 100;
downloadBar.Value = (int)e.BytesReceived / 100;
}
public static class EncryptorDecryptor
{
public static int key = 3;
public static string EncryptDecrypt(string textToEncrypt)
{
StringBuilder inSb = new StringBuilder(textToEncrypt);
StringBuilder outSb = new StringBuilder(textToEncrypt.Length);
char c;
for (int i = 0; i < textToEncrypt.Length; i++)
{
c = inSb[i];
c = (char)(c ^ key);
outSb.Append(c);
}
return outSb.ToString();
}
}
}
Thanks in advance, I'm very new to C# and this is my first real project.

Where did you get 8a33b8a537d4e17ec4ac7041df43d892821c16dc15cf84fb33a672ab76c72119126f9c4849cf55423b0112c4b4 from?
Running it through the decoder with the specified key of '3' gives:
;0ab0gf4b47g7g:;22g2;e0b4b41225:7767032`a
Clearly nothing like a valid URI. I've tried a couple of quick things to see if I can get something sensible out (like converting the value from hex to bytes) but nothing reasonable appears.
If you're new to C# and this is your first real project, you should break it down into much easier pieces. Make sure you can take any string, encode it with the EncryptorDecryptor and then decode the result to get the same value. Then, set aside the encryption and make sure you can download any normal file from your site. When you have both working (and understand how they work and more importantly, how they behave when they fail) combine the two.