Paip. Improve Performance ---.net listbox use BeginUpdate and EndUpdate

Use the default this. listBox1.Items. Add (line );

 

The result is as follows:
1 million rows of data: 1 second
Row 3: 10 thousand seconds
0.1 million rows: 40 seconds

 

Query Information, using BeginUpdate and EndUpdate can improve performance.
Therefore, BeginUpdate and EndUpdate are used.

The result is as follows:

The result is as follows:
1 million lines of data: 0.5 seconds
Row 3: 4 seconds
Row 0.1 million: 44 seconds

 

Conclusion:
--------
When BeginUpdate and EndUpdate are used in thousands of rows, the performance can be improved by no factor ......
However, when there are hundreds of thousands and hundreds of thousands of data, it is even 10 thousand slower than the default method ......

 

 

 

--------------- Main source code :-----------

 

 

Int loadRecNum = 0;
Long curtime = 0;
Private void button#click (object sender, EventArgs e)
{
OpenFileDialog openFileDlg = new OpenFileDialog ();
OpenFileDlg. Title = "Please select :";
OpenFileDlg. Filter = "*. * | *.*";
OpenFileDlg. ShowDialog ();
If (openFileDlg. CheckFileExists)
{
If (openFileDlg. FileName. Equals (""))
Return;
String pathYZM = openFileDlg. FileName;

 

// C452308 add txt2list
Thread t = new Thread (new ParameterizedThreadStart (
Delegate (object obj)
{
LoadRecNum = 0;
Curtime = DateTime. Now. Ticks;

// C45 big txt

// Pass the file path and file name to the StreamReader constructor
StreamReader sr = new StreamReader (pathYZM );

// Read the first line of text
String line = sr. ReadLine ();

// Continue to read until you reach end of file
Int n = 0;
// ListBox1.Visible = false;

ListBox1.Invoke (new EventHandler (delegate
{
This. listBox1.BeginUpdate ();
}));

Form1 fm = (Form1) obj;
While (line! = Null)
{
// Thread. Sleep (5 );
// Console. WriteLine ("--" + n. ToString () + ":" + line );
N ++;

// Write the lie to console window
If (n % 1000 = 0)
{
Console. WriteLine ("--" + n. ToString () + ":" + line );
// ListBox1.Invoke (new EventHandler (delegate
//{
// ListBox1.EndUpdate ();
/// This. listBox1.BeginUpdate ();
//}));

}

Add2List (line );

Int readNum = this. settingForm. getReadNum ();
If (n> = readNum)
Break;
// Read the next line
Line = sr. ReadLine ();
// If (line = null)
// ListBox1.Invoke (new EventHandler (delegate
//{
// ListBox1.EndUpdate ();

//}));

}
// ListBox1.EndUpdate ();
// ListBox1.Visible = true;
// Close the file
Sr. Close ();

ListboxEndUpdate ();
/// C45

 

LoadRecNum ++;
Label8.Invoke (new EventHandler (delegate
{
Label8.Text = "loaded:" + loadRecNum. ToString ();

}));

Long nowtime = DateTime. Now. Ticks;
Float span = (float) (nowtime-curtime)/(float) 10000000 ));
Int spanint = (int) span;
Label9.Invoke (new EventHandler (delegate
{
Label9.Text = "in use:" + span. ToString () + "seconds ";

}));

}

));
T. Name = "-- start txt2list thread ";
T. IsBackground = true;
T. Start (this );

 

 
}

 

 

}

Private void ListboxEndUpdate ()
{
ListBox1.Invoke (new EventHandler (delegate
{
ListBox1.EndUpdate ();

}));
}
Int nc45 = 0;
Public void add2List (string line)
{

AccFilter4ihush af = new accFilter4ihush ();

If (af. filterOK (line ))
{
LoadRecNum ++;
// BeginInvoke
ListBox1.Invoke (new EventHandler (delegate
{

// Thread. Sleep (5000 );
This. listBox1.Items. Add (line );
// Console. WriteLine ("-- add2List:" + nc45.ToString () + ":" + line );
Nc45 ++;
}));

// Label8.Invoke (new EventHandler (delegate
//{
// Label8.Text = "loaded:" + loadRecNum. ToString ();

//}));

// Long nowtime = DateTime. Now. Ticks;
// Float span = (float) (nowtime-curtime)/(float) 10000000 ));
// Int spanint = (int) span;
// Label9.Invoke (new EventHandler (delegate
//{
// Label9.Text = "in use:" + spanint. ToString () + "seconds ";

//}));

}

// This. listView1.Items. Add (item );

}