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C # Threading using invoke, form freeze

I am trying to use threads and prevent the program from freezing while the thread is busy. It should show progress (record 0/1), and not just show the result after its completion, thereby freezing the form.

In the current program, I try to write in a text field and actually see constant progress, and the tasks of another thread cannot influence the form.

Now I have the opportunity to write to the text box with the stream using invoke, but it shows only the result (the form freezes when the stream is busy) and the form freezes.

Form Image:

enter image description here

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.Threading;

namespace MultiThreading
{
public partial class MultiThreading : Form
{
    public MultiThreading()
    {
        InitializeComponent();
    }

    Thread writeOne, writeTwo;

    private void writeText(TextBox textBox, string text)
    {
        if (textBox.InvokeRequired)
        {
            textBox.BeginInvoke((MethodInvoker)delegate()
            {
                for (int i = 0; i < 500; i++)
                {
                    textBox.Text += text;
                }
            });
        }
        else
        {
            for (int i = 0; i < 500; i++)
            {
                textBox.Text += text;
            }
        }
    }
    private void btnWrite1_Click(object sender, EventArgs e)
    {
        writeOne = new Thread(() => writeText(txtOutput1, "0"));
        writeOne.Start();
    }

    private void btnWrite2_Click(object sender, EventArgs e)
    {
        writeTwo = new Thread(() => writeText(txtOutput2, "1"));
        writeTwo.Start();
    }

    private void btnClear1_Click(object sender, EventArgs e)
    {
        txtOutput1.Clear();
    }

    private void btnClear2_Click(object sender, EventArgs e)
    {
        txtOutput2.Clear();
    }

    private void btnWriteBoth_Click(object sender, EventArgs e)
    {
        writeOne = new Thread(() => writeText(txtOutput1, "0"));
        writeTwo = new Thread(() => writeText(txtOutput2, "1"));

        writeOne.Start();
        writeTwo.Start();
    }

    private void btnClearBoth_Click(object sender, EventArgs e)
    {
        txtOutput1.Clear();
        txtOutput2.Clear();
    }
}

}

EDIT:

Btw, for anyone who wonders, I'm new to multithreading, and I'm just trying to write a little program to figure out how to do this.

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private void writeText(TextBox textBox, string text)
    {
        for (int i = 0; i < 500; i++)
        {
            Invoke(new MethodInvoker(() =>
            {
                textBox.Text += text;
                Thread.Sleep(2);
            }));
        }

    }

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2:

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private void writeText(TextBox textBox, string text)
    {
        for (int i = 0; i < 500; i++)
        {
            Invoke(new MethodInvoker(() =>
            {
                textBox.Text += text;
                Thread.Sleep(2);
            }));
        }

    }

3:

Sumeet

Application.DoEvents();

(, s,.DoEvent , , : P), , .

, :)

* 5 ,

private void writeText(TextBox textBox, string text)
    {
        for (int i = 0; i < 57; i++)
        {
            Invoke(new MethodInvoker(() =>
            {
                textBox.Text += text;
                Thread.Sleep(5);
                Application.DoEvents();
            }));
        }

    }
private void btnNewThread_Click(object sender, EventArgs e)
    {
        Random random = new Random();
        int[] randomNumber = new int[5];
        for (int i = 0; i < 5; i++)
        {
            randomNumber[i] = random.Next(2, 9);
            new Thread(() => writeText(txtOutput1, randomNumber[i-1].ToString())).Start();
            new Thread(() => writeText(txtOutput2, randomNumber[i-1].ToString())).Start();
        }
    }
+5
6

! .

, , . , Application.DoEvents :

textBox.Text += text;
Application.DoEvents();

p.s.: else If/Else, , , , , , , - .

+6

, , .

for (int i = 0; i < 500; i++){
    string text = ""+i;
    textBox.BeginInvoke((MethodInvoker)delegate()
            {
                textBox.Text += text;
            });
}
+5

, , , , . , , , , .

, BeginInvoke ( Invoke) .

private void writeText(TextBox textBox, string text)
{
    for (int i = 0; i < 500; i++)
    {
        Invoke(new MethodInvoker(() =>
        {
            textBox.Text += text;
        }));
    }
}

, , / .. . , InvokeRequired. , , UI, .

+3

.

BeginInvoke().

.

+2

, .

. TextBox , , (TextBox) , . , , . TextBoxes .

, paint, , , TextBox :

string str = string.Empty;
public void DoStuff()
{
    System.Threading.ThreadPool.QueueUserWorkItem(WorkerThread);
}

void WorkerThread(object unused)
{
    for (int i = 0; i < 1000; i++)
    {
        str += "0";
        if (updatedUI)
        {
            updatedUI = false;
            BeginInvoke(new Action<string>(UpdateUI), str);
        }
    }
    BeginInvoke(new Action<string>(UpdateUI), str);
}

private volatile bool updatedUI = true;
void textbox1_Paint(object sender, PaintEventArgs e) // event hooked up in Form constructor
{
    updatedUI = true;
}

void UpdateUI(string str)
{
    textBox1.Text = str;
}

On the other hand, if UI animation is your goal, you should probably use something other than a TextBox. It is simply not designed to handle updates so often. There may be some optimizations for text rendering that you could do for your specific use case.

0
source

You should never use string in high volume applications. UI or not. Multithreading or not.

You must use StringBuilder to accumulate the string. and then assign

tb.Text = sb.ToString();
0
source

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