Develop Reference

C# Textbox properties do not update

I have a simple form with a text box, a command button and a couple of timers. The only purpose of the form is to advise the user what is happening. The program executes all the code as required EXCEPT for the textbox changes. I know the code to implement the textbox changes is executed because the form and the command button properties change as required.
I have added this.refresh and this.textbox1.refresh to no avail.
I am new to C# and most of the time I do not have Visual Studios available, so your assistance would be most appreciated. I have read other posts on this topic and probably the answer has already been given, but I have not understood the solution.
The simplified code is given below:
//PROGRAM.CS
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Windows.Forms;
using WindowsFormsApplication1;
namespace PostBinaryFile
{
static class Program
{
/// The main entry point for the application.
[STAThread]
static void Main(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1(args));
}
}
}
//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.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using System.Web;
using System.Net;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
string sUrl;
string sFileName;
string sCorNo;
public Form1(string[] args)
{
sUrl = args[0];
sFileName = args[1];
sCorNo = args[2];
InitializeComponent();
timer1.Enabled = true;
timer1.Start();
timer2.Enabled = true;
timer2.Start();
}
public void PostCode()
{
InitializeComponent();
string sToken;
string sPath;
const string boundary = "----WebKitFormBoundaryePkpFF7tjBAqx29L";
try
{
//Do all general code work here.
//Alter form to show successful post to web
this.button1.Visible = true;
this.button1.Enabled = true;
this.BackColor = System.Drawing.Color.FromArgb(189,194,241);
this.textBox1.Text = sCorNo + " Outlook file saved to FuseDMS."; // this code is executed but is not reflected on the Form
this.textBox1.BackColor= System.Drawing.Color.FromArgb(189,194,241); // this code is executed but is not reflected on the Form
}
private void timer1_Tick(object sender, EventArgs e)
{
timer1.Stop();
timer1.Enabled = false;
PostCode();
}
private void timer2_Tick(object sender, EventArgs e)
{
timer2.Stop();
timer2.Enabled = false;
this.textBox1.Text = "Saving Message " + sCorNo + ".";
}
private void button1_Click(object sender, EventArgs e)
{
Application.Exit();
}
}
}

As #DavidG pointed out, you should not call InitializeComponent() periodically or even more then once, do it as the first thing in the constructor.
This is because any controls and properties that you add/set from the designer are created and initialized in this method.
Another thing to point out is Timer.Enabled = true and Timer.Start() effectively do the same thing
From: System.Windows.Forms.Timer.Enabled
Calling the Start method is the same as setting Enabled to true. Likewise, calling the Stop method is the same as setting Enabled to false.

Both timers namely timer1 and timer2 fire asynchronously and run on separate threads which are completely independent of each other. Even if timer2's tick event would be setting/refreshing the text appropriately through below code:
this.textBox1.Text = "Saving Message " + sCorNo + ".";
you can never say with guarantee that it will happen only after timer1's tick event has completed the execution of its callback method. In all likelyhood your above code is setting the text property of a dangling text box instance as your InitializeComponent function (being called from timer1's tick event) must be reinstantiating a new instance of all the form controls.
Your call to InitializeComponent function in PostCode method which gets called from tick event of timer1's tick event isn't right as it resets all the instances of form controls to new ones. It should be called only once in the constructor of the form. Just remove that piece of code and you should be good. Your PostCode function should actually look like this after you get rid of that piece of code:
public void PostCode()
{
string sToken;
string sPath;
const string boundary = "----WebKitFormBoundaryePkpFF7tjBAqx29L";
try
{
//Do all general code work here.
//Alter form to show successful post to web
this.button1.Visible = true;
this.button1.Enabled = true;
this.BackColor = System.Drawing.Color.FromArgb(189,194,241);
this.textBox1.Text = sCorNo + " Outlook file saved to FuseDMS."; // this code is executed but is not reflected on the Form
this.textBox1.BackColor= System.Drawing.Color.FromArgb(189,194,241); // this code is executed but is not reflected on the Form
}

Calling BackgroundWorker.ReportProgress from an instantiated class? C#

I am writing a program that involves some heavy conversion of an Excel file into a very specifically formatted flat file. There are over 50,000 rows that need converted, so needless to say, it will take a while to process.
With that said, using a BackgroundWorker would make the most sense.
Everything I have executes properly and works fine except for one issue: trying to call the BackgroundWorker.ReportProgress() method from an instantiated class to update a counter on the parent Form.
If I'm not making sense, maybe my code will make more sense:
The Processing GUI Form:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.IO;
using System.Windows.Forms;
namespace CityTaxImport
{
public partial class Processing : Form
{
string s_sourceFile;
bool b_fileSaved;
CityConvert convert = new CityConvert();
public Processing(string s_incomingPath)
{
BackgroundWorker bg_Taxes = new BackgroundWorker();
s_sourceFile = s_incomingPath;
//background worker
bg_Taxes.DoWork += new DoWorkEventHandler(bg_Taxes_DoWork);
bg_Taxes.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bg_Taxes_RunWorkerCompleted);
bg_Taxes.ProgressChanged += new ProgressChangedEventHandler(bg_Taxes_ProgressChanged);
bg_Taxes.WorkerSupportsCancellation = true;
bg_Taxes.WorkerReportsProgress = true;
InitializeComponent();
bg_Taxes.RunWorkerAsync();
}
#region METHODS
#region BACKGROUND WORKER
//do work/runworker Async stuff
private void bg_Taxes_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker bg_Taxes = sender as BackgroundWorker;
CityConvert convert = new CityConvert();
convert.ConvertFile(s_sourceFile);
}
//when the worker completes, let user know, end program
private void bg_Taxes_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
pb_Progress.MarqueeAnimationSpeed = 0;
//lets the user know the file is done and prompts them on where to save it at
if (MessageBox.Show(this, "The file has been created.\nChoose where you would like to save it.",
"Conversion Finished", MessageBoxButtons.OK, MessageBoxIcon.Asterisk) == DialogResult.OK)
{
while (b_fileSaved != true)
{
SaveFile();
}
}
}
//used to update the progress count
public void bg_Taxes_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
//RIGHT HERE IS WHAT SHOULD UPDATE THE COUNTER
lb_recordCount.Text = convert.i_RowCount.ToString();
}
#endregion
And now the class with all of the hard work:
using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;
using System.IO;
using Excel = Microsoft.Office.Interop.Excel;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using System.Text.RegularExpressions;
namespace CityTaxImport
{
class CityConvert
{
#region VARIABLES AND OBJECTS AND ALL THE OTHER VARS AND CHARS
//the Excel squad
Excel._Application xl_app;
Excel._Workbook xl_wrkBk;
Excel._Worksheet xl_wrkSht;
//our friend object Type.Missing
private object o_miss = Type.Missing;
//dataset and table
private DataSet ds_taxes;
private DataTable dt_taxes;
private DataRow dr_taxes;
//strings and counts and stuff
private string s_sourceFile;
private int i_xlRowTotal;
private int i_xlRowCount;
private int i_dtRowCount;
private string s_output;
public int i_RowCount{get; set;}
#endregion
#region METHODS
//the initial convert file method called by the main window
public bool ConvertFile(string s_selectedFile)
{
s_sourceFile = s_selectedFile;
CreateDataSet();
OpenExcel();
PopulateDateSet();
WriteFile();
CloseExcel();
return true;
}
//builds the dataset to use
//creates the column names that will be written into and then written to the flat file
//SOME WILL JUST BE SPACES
private void CreateDataSet()
{
ds_taxes = new DataSet();
ds_taxes.Tables.Add("Taxes");
dt_taxes = new DataTable();
dt_taxes = ds_taxes.Tables["Taxes"];
dt_taxes.Columns.Add("Pr_Ward");
dt_taxes.Columns.Add("Pr_Block");
dt_taxes.Columns.Add("Pr_Map");
dt_taxes.Columns.Add("Pr_Parcel");
dt_taxes.Columns.Add("Pr_LeaseHold");
dt_taxes.Columns.Add("ParFill");
dt_taxes.Columns.Add("Stub");
dt_taxes.Columns.Add("Pa_Amt");
dt_taxes.Columns.Add("TOTFLG");
dt_taxes.Columns.Add("Pr_WardBATCH");
dt_taxes.Columns.Add("BSEQ");
dt_taxes.Columns.Add("TRANSNO");
dt_taxes.Columns.Add("TRANCD");
dt_taxes.Columns.Add("Pa_BatchDate_TD");
dt_taxes.Columns.Add("Pa_BatchDate_ED");
dt_taxes.Columns.Add("BUSDATE");
dt_taxes.Columns.Add("METH");
dt_taxes.Columns.Add("Pa_Amt2");
dt_taxes.Columns.Add("Payment_ID");
dt_taxes.Columns.Add("OWNSEQ");
dt_taxes.Columns.Add("Pr_OwnerInfo1");
}
//time to populate the dataset form the info from the ExcelSheet
private void PopulateDateSet()
{
//
i_xlRowTotal = 2;
while (xl_wrkSht.Cells.Range["A" + i_xlRowTotal].Value2 != null)
{
i_xlRowTotal++;
}
i_xlRowCount = 2;
i_xlRowTotal = i_xlRowTotal - 2;
for (i_dtRowCount = 0; i_dtRowCount < (i_xlRowTotal); ++i_dtRowCount)
{
//this is used to make conversions of the strings to add paddings, length modifiers, what have you...
//all that fun stuff
dr_taxes = dt_taxes.NewRow();
dr_taxes["Pr_Ward"] = Convert.ToString(xl_wrkSht.Cells.Cells.Range["P" + (i_xlRowCount)].Value2);
dr_taxes["Pr_Block"] = Convert.ToString(xl_wrkSht.Cells.Range["Q" + (i_xlRowCount)].Value2);
dr_taxes["Pr_Map"] = Convert.ToString(xl_wrkSht.Cells.Range["R" + (i_xlRowCount)].Value2);
dr_taxes["Pr_Parcel"] = Convert.ToString(xl_wrkSht.Cells.Range["S" + (i_xlRowCount)].Value2);
dr_taxes["Pr_LeaseHold"] = Convert.ToString(xl_wrkSht.Cells.Range["T" + (i_xlRowCount)].Value2);
dr_taxes["ParFill"] = #" ";//12 spaces
dr_taxes["Stub"] = #" ";//10 spaces ALWAYS
dr_taxes["Pa_Amt"] = AppendAmt();
dr_taxes["TOTFLG"] = "N";
dr_taxes["Pr_WardBATCH"] = AppendWard();
dr_taxes["BSEQ"] = AppendBSEQ();
dr_taxes["TRANSNO"] = "000000000";
dr_taxes["TRANCD"] = "P";
dr_taxes["Pa_BatchDate_TD"] = AppendBatchDates();
dr_taxes["Pa_BatchDate_ED"] = AppendBatchDates();
dr_taxes["BUSDATE"] = #" "; //6 spaces
dr_taxes["METH"] = "Check";
dr_taxes["Pa_Amt2"] = AppendAmt();
dr_taxes["Payment_ID"] = AppendID();
dr_taxes["OWNSEQ"] = "000";
dr_taxes["Pr_OwnerInfo1"] = AppendOwner();
dt_taxes.Rows.Add(dr_taxes);
++i_xlRowCount;
i_RowCount = i_xlRowCount;
//RIGHT HERE IS WHERE I WANT TO CALL THE
Processing.bg_Taxes.ReportProgress() //method
}
}
I have tried Processing.bg_Taxes.ReportProgress(); but I get the Object reference is required for the non-static...method error (which I understand what that is.)
I have also looked at a lot of other Q&As on here about the using BackgroundWorkers however none of them seem to quite answer my question or I am just not getting it (which may be the issue as well).
My questions are, then: is there a way to call that method without making my BackgroundWorker static?
And with that: is there any problem with MAKING it static (I have always been told avoid static methods and what have you when writing code).
And finally: am I missing something in my logic here about how exactly I should be going about this? Is there another more "best practice" way?
Any help or advice is appreciated.
Thank you all in advance.
UPDATE
I ended up solving my problem by just some of the essential methods over to the Form class and altering my code from there. Just wanted to throw it out there and thank everyone for pointing in me in the right directions.

Displaying received data from serial port

I have a problem working with the serial data received event handler. Half of the time the data displays on the textbox and half of the time does not. It should be the issue with cross thread operation.
This is my Arduino code:
int Loop = 1;
void setup() {
Serial.begin(9600);
}
void loop() {
Serial.println(Loop);
Loop++;
delay(1000);
}
And here is my C# code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO.Ports;
namespace arduino_test
{
public partial class Form1 : Form
{
SerialPort sPort;
public Form1()
{
InitializeComponent();
initialiseArduino();
}
public void initialiseArduino()
{
sPort = new SerialPort();
sPort.BaudRate = 9600;
sPort.PortName = "COM16";
sPort.Open();
//sPort.DataReceived += new SerialDataReceivedEventHandler(sPort_DataReceived);
}
void sPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
SerialPort sp = (SerialPort)sender;
string data = sp.ReadExisting();
displayMessage(data);
}
public void displayMessage(string data)
{
if (InvokeRequired)
{
this.Invoke(new Action<string>(displayMessage), new object[] { data });
return;
}
textBox1.Text = data;
}
private void button1_Click(object sender, EventArgs e)
{
while (true)
{
string data = sPort.ReadLine();
textBox1.Text = data;
}
}
}
}
When i use the serial data received event handler, it gives me that problem even after invoking.
So i tried running a same thread operation by clicking a button and it works perfectly fine.
Can anybody advise me on what have i done wrong?

The obvious difference and the cause of your problem is the two different way you do this. You use ReadExisting() in your DataReceived event handler but ReadLine() in your Click event handler.
ReadExisting() just doesn't do what you hope it does, you only get 1 or 2 characters. Whatever is "existing", never much since the DataReceived event fires quickly and modern desktop computers are very fast. Then the event fires again and you read another 1 or 2 chars. Your TextBox only shows whatever came last.
Use ReadLine() instead.

You might want to update displayMessage method with
public void displayMessage(string data)
{
if (InvokeRequired)
{
this.Invoke(new Action<string>(displayMessage), new object[] { data });
return;
}
**textBox1.Text = textBox1.Text + data;**
}
In this way you'll never clear the textBox1 content and you'll have all values.
Please take in consideration (depends by your data) that your incoming data could contain control chars or other things that could not be nicely shown in textbox control.

C# Thread error

So im attempting to create a auto typer. And the problem is if i spam the message, And click the application to stop the spam it just freezes up. I as then told i need to use Threads. So i had a read around and this is what i came up with:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Threading;
namespace tf2trade
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public bool started = true;
private void spam()
{
string test = text1.Text;
Thread.Sleep(2000);
while (started == false)
{
foreach (char c in test)
{
SendKeys.Send(c.ToString());
}
SendKeys.Send("{ENTER}");
}
}
Thread test = new Thread(spam);
private void richTextBox1_TextChanged(object sender, EventArgs e)
{
}
private void submit_Click(object sender, EventArgs e)
{
if (started == true)
{
started = false;
submit.Text = "Stop";
submit.Refresh();
spam();
}
else
{
started = true;
submit.Text = "Start";
}
}
}
}
Now this code gives me the error:
A field initializer cannot reference the non-static field, method, or property 'tf2trade.Form1.spam()'
What did i do wrong? :(
Thanks in advance,
Alana.

Honestly I wouldn't waste your time troubleshooting this error. Instead, consider using one of the existing approaches to writing multi-threaded applications in .NET . The technology you use will depend on the type of problem you are trying to solve. For short/quick tasks consider using:
thread pool
.net task library
If you are creating a "long" running task you could create 1 or more native threads, but I wouldn't recommend doing this until you have a better understanding of what you are doing. There are a lot of pitfalls. For example, A lot of developers think more threads equals better performance... this is not true.
REFERENCES
thread pool:
http://msdn.microsoft.com/en-us/library/system.threading.threadpool(v=vs.110).aspx
tasks: http://msdn.microsoft.com/en-us/library/dd460717(v=vs.110).aspx
native thread: http://msdn.microsoft.com/en-us/library/system.threading.thread(v=vs.110).aspx

Access Form1 elements from filesystemeventhandler

I have a program that is checking for changes in a file, then once the file changes it reads it and updates some labels. "However it crashes because I am trying to change elements in a thread from a different thread" ~ Or so I think. Any ideas?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Windows.Forms;
using System.IO;
using System.Threading.Tasks;
namespace RoomAutomation
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public void readfile_Click(object sender, EventArgs e)
{
string[] lines = System.IO.File.ReadAllLines(#"C:\Users\Dandrews\control.txt");
FileSystemWatcher fsw = new FileSystemWatcher();
fsw.Path = #"C:\Users\Dandrews\";
fsw.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite |
NotifyFilters.DirectoryName | NotifyFilters.FileName;
fsw.Changed += new FileSystemEventHandler(OnChanged);
fsw.EnableRaisingEvents = true;
if (lines[0] == "1:lights")
{
Lights.Text = "Lights are on.";
}
if (lines[0] == "0:lights")
{
Lights.Text = "Lights are off.";
}
if (lines[1] == "1:camera")
{
Camera.Text = "Camera is on.";
}
if (lines[1] == "0:camera")
{
Camera.Text = "Camera is off.";
}
if (lines[2] == "1:speakers")
{
Speakers.Text = "Speakers are on.";
}
if (lines[2] == "0:speakers")
{
Speakers.Text = "Speakers are off.";
}
if (lines[3] == "1:playlist")
{
Playlist.Text = "Playlist is on.";
}
if (lines[3] == "0:playlist")
{
Playlist.Text = "Playlist is off.";
}
}
private void OnChanged(object source, FileSystemEventArgs e)
{
Console.Write("Changes");
//Lights.Text = "New label Text";
}
}
}
`

That's because FileSystemWatcher raises its events on a threadpool thread. Which is the natural way, those file system events happen asynchronously. You cannot directly access any UI components in the event handler, they are not thread-safe. The InvalidOperationException is there to remind you that you can't.
Fixing it takes adding a single line of code:
fsw.SynchronizingObject = this;
Which forces FileSystemWatcher to marshal the event handler call to the thread that created the form, the UI thread. This is not necessarily the best solution, there's a great deal of overhead involved in marshaling the call. But you'll be quite okay with this solution since you have to marshal for each event anyway with the code you have now.

.NET 2.0 and up doesn't allow you to access UI elements from other threads. You have to call invoke the code you want to run on the control. If you're porting.NET 1.1 code, here's a simple hack to make your life easier:
http://codebetter.com/jeremymiller/2006/11/06/using-anonymous-methods-with-control-invoke/