Csharp/C Sharp/Thread/Thread and GUI
Demonstrates hiding a form and then doing background processing in a second thread
<source lang="csharp"> /* C# Programming Tips & Techniques by Charles Wright, Kris Jamsa Publisher: Osborne/McGraw-Hill (December 28, 2001) ISBN: 0072193794
- /
// HideForm.cs -- Demonstrates hiding a form and then doing background // processing in a second thread. // // Compile this program with the following command line: // C:>csc HideForm.cs using System; using System.Windows.Forms; using System.Threading; namespace HideForm {
public class HideForm : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
public HideForm()
{
Text = "A Simple Form";
button1 = new Button ();
SuspendLayout();
button1.Text = "Cancel";
button1.Name = "button1";
button1.Size = new System.Drawing.Size (72, 30);
button1.Location = new System.Drawing.Point ((ClientRectangle.Width - button1.Size.Width) / 2, ClientRectangle.Height - 35);
Controls.AddRange(new System.Windows.Forms.Control[] {this.button1});
button1.Click += new System.EventHandler(OnClickButton1);
this.Closed += new System.EventHandler(OnClickButton1);
ResumeLayout (false);
this.Visible = false;
}
[STAThread]
static void Main()
{
HideForm form = new HideForm();
Thread delay = new Thread (new ThreadStart(form.DelayVisible));
delay.Start ();
Application.Run();
}
public void DelayVisible ()
{
while (true)
{
Thread.Sleep (2500);
DialogResult result = MessageBox.Show ("Display Form?", "Display", MessageBoxButtons.YesNoCancel);
switch (result)
{
case DialogResult.Yes:
this.ShowDialog();
return;
case DialogResult.No:
continue;
case DialogResult.Cancel:
Application.Exit ();
break;
}
return;
}
}
private void OnClickButton1(object sender, System.EventArgs e)
{
Application.Exit ();
}
}
}
</source>
Thread and GUI
<source lang="csharp"> /* Professional Windows GUI Programming Using C# by Jay Glynn, Csaba Torok, Richard Conway, Wahid Choudhury,
Zach Greenvoss, Shripad Kulkarni, Neil Whitlow
Publisher: Peer Information ISBN: 1861007663
- /
using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; using System.Threading; namespace Wrox.WindowsGUIProgramming.Chapter9 {
/// <summary>
/// Summary description for Form1.
/// </summary>
///
struct _threadstart
{
public ThreadStart threadstart;
public DateTime dt;
}
public class frmWasteTime : System.Windows.Forms.Form
{
private System.Windows.Forms.Button butWasteTime;
private System.Windows.Forms.TextBox textBox1;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ruponentModel.Container components = null;
private System.Windows.Forms.ListBox lbThreads;
private System.Windows.Forms.TextBox txtNoOfThreads;
private System.Windows.Forms.Button btThreadStart;
private System.IAsyncResult m_EndInvoke = null;
public frmWasteTime()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
this.Show();
//TakeTime();
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.butWasteTime = new System.Windows.Forms.Button();
this.textBox1 = new System.Windows.Forms.TextBox();
this.lbThreads = new System.Windows.Forms.ListBox();
this.txtNoOfThreads = new System.Windows.Forms.TextBox();
this.btThreadStart = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// butWasteTime
//
this.butWasteTime.Location = new System.Drawing.Point(88, 32);
this.butWasteTime.Name = "butWasteTime";
this.butWasteTime.TabIndex = 0;
this.butWasteTime.Text = "Waste Time";
this.butWasteTime.Click += new System.EventHandler(this.butWasteTime_Click);
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(184, 24);
this.textBox1.Name = "textBox1";
this.textBox1.TabIndex = 1;
this.textBox1.Text = "";
//
// lbThreads
//
this.lbThreads.Location = new System.Drawing.Point(8, 64);
this.lbThreads.Name = "lbThreads";
this.lbThreads.Size = new System.Drawing.Size(280, 277);
this.lbThreads.TabIndex = 2;
//
// txtNoOfThreads
//
this.txtNoOfThreads.Location = new System.Drawing.Point(8, 352);
this.txtNoOfThreads.Name = "txtNoOfThreads";
this.txtNoOfThreads.TabIndex = 3;
this.txtNoOfThreads.Text = "";
//
// btThreadStart
//
this.btThreadStart.Location = new System.Drawing.Point(128, 352);
this.btThreadStart.Name = "btThreadStart";
this.btThreadStart.Size = new System.Drawing.Size(160, 23);
this.btThreadStart.TabIndex = 4;
this.btThreadStart.Text = "Start";
this.btThreadStart.Click += new System.EventHandler(this.btThreadStart_Click);
//
// frmWasteTime
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(296, 390);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.btThreadStart,
this.txtNoOfThreads,
this.lbThreads,
this.textBox1,
this.butWasteTime});
this.Name = "frmWasteTime";
this.Text = "Lock Form";
this.Paint += new System.Windows.Forms.PaintEventHandler(this.painting);
this.ResumeLayout(false);
}
#endregion
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new frmWasteTime());
}
private void TakeTime()
{
int j = 0;
for(int i=0;i<320-j;i++)
{
System.Diagnostics.Debug.Write(i);
}
j++;
}
private void butWasteTime_Click(object sender, System.EventArgs e)
{
IAsyncResult m_EndInvoke2 = null;
ThreadStart threadstart = new ThreadStart(TakeTime);
m_EndInvoke = threadstart.BeginInvoke(new AsyncCallback(MethodBeginInvoke), String.Copy("test"));
ThreadStart threadstart2 = new ThreadStart(TakeTime);
m_EndInvoke2 = threadstart.BeginInvoke(new AsyncCallback(MethodBeginInvoke), null);
//m_EndInvoke.AsyncWaitHandle.WaitOne();
threadstart.EndInvoke(m_EndInvoke);
threadstart.EndInvoke(m_EndInvoke2);
/*while(true)
{
if(m_EndInvoke.IsCompleted)
MessageBox.Show("finally!!!");
break;
}*/
}
private void MethodBeginInvoke(System.IAsyncResult ar)
{
if(ar.rupletedSynchronously)
MessageBox.Show("TakeTime() called synchronously");
else
MessageBox.Show("TakeTime() called asynchronously");
}
protected override void OnPaint(PaintEventArgs pe)
{
System.Diagnostics.Debug.Write("Paint event called");
}
private void painting(object sender, System.Windows.Forms.PaintEventArgs e)
{
System.Diagnostics.Debug.Write("Paint event called");
}
//System.Threading.ThreadStart[] threads;
//DateTime[] dateTimeThread;
_threadstart[] th;
DateTime dtStart;
DateTime dtEnd;
private void btThreadStart_Click(object sender, System.EventArgs e)
{
th = new _threadstart[Convert.ToInt32(txtNoOfThreads.Text)];
//threads = (ThreadStart[])Array.CreateInstance(typeof(ThreadStart), Convert.ToInt16(txtNoOfThreads.Text));
//dateTimeThread = (DateTime[])Array.CreateInstance(typeof(DateTime), threads.Length);
dtStart = DateTime.Now;
for(int i = 0; i < th.Length; i++)
{
th[i].threadstart = new ThreadStart(TakeTime);
th[i].threadstart.BeginInvoke(new AsyncCallback(ThreadFinished), i);
th[i].dt = DateTime.Now;
}
/*while(true)
{
for(int i = 0; i < threads.Length; i++)
{
if((threads[i].ThreadState == System.Threading.ThreadState.Suspended) && finished[i].Equals(false))
{
//put something into the listbox
lbThreads.Items.Insert(i, "Thread "+i+" finished - "+(DateTime.Now.Subtract(dateTimeThread[i])));
finished[i] = true;
}
Refresh();
}
}*/
}
void FinalCallback(string blank)
{
dtEnd = DateTime.Now.Subtract(new TimeSpan(dtStart.Ticks));
lbThreads.Items.Add("Total Thread Time: "+((dtEnd.Minute*60)+dtEnd.Second).ToString()+" seconds");
lbThreads.Items.Add("Average Thread Time: "+(((dtEnd.Minute*60)+dtEnd.Second)/th.Length)+" seconds");
}
void UpdateListbox(string listboxText)
{
lbThreads.Items.Add(listboxText);
}
delegate void ItemAdd(string item);
private void ThreadFinished(IAsyncResult ar)
{
ItemAdd ia = new ItemAdd(UpdateListbox);
ItemAdd ib = new ItemAdd(FinalCallback);
int i = (int)ar.AsyncState;
string state = "Thread "+(i+1)+" finished - "+(DateTime.Now.Subtract(th[i].dt)).ToString();
//put something into the listbox
if(lbThreads.InvokeRequired)
{
lbThreads.Invoke(ia, new Object[] {state});
}
else
{
lbThreads.Items.Add(state);
}
if(i==(th.Length-1)) lbThreads.Invoke(ib, new Object[]{""});
}
}
}
</source>
