更改C＃中的label.text

Question

I am a newbie with C#. I am trying to show how much times the button is clicked, here is my code below:

private void ClickMebutton_Click(object sender, EventArgs e)
{
      int i = 0;     
      while (true)    
       {              
         label1.Text = i.ToString();
         i += 1;   
       }
}

code runs fine, but label.text is not changing when I clicked the button. I also cannot identify any problem by using break points. Can anyone please help me out?

Answer 1

int i = 0; // 1

private void ClickMebutton_Click(object sender, EventArgs e)
{
    i++; // 3
    label1.Text = i.ToString();
}

Comments:

1. Store counter outside of event handler body. Otherwise, it will reset to 0 each time you click on the button. You can also parse label text instead of storing counter in the class field.
2. Remove infinite while loop
3. Increment counter before you assign text. Otherwise, after first click you will have 0

Solution with parsing label text:

Note that initially you should set label text to "0" . Do it in the designer. Thus after application start label will show correct information - button was clicked zero times.

private void ClickMebutton_Click(object sender, EventArgs e)
{
    int i = Int32.Parse(label1.Text);
    i++;
    label1.Text = i.ToString();
}

Answer 2

you should define i publicly

 private int i = 0;     
private void ClickMebutton_Click(object sender, EventArgs e)
{

     i++;          
     label1.Text = i.ToString();


 }

Answer 3

It seems that it is not changing since your are having an infinite loop here:

 while (true)

If you put your break point on that spot , you are just looping and looping that's why you cannot see the changes. Make this:

int i = 0;

A global variable, and remove your infinite loop which you don't really need on your logic:

private int i = 0;     
private void ClickMebutton_Click(object sender, EventArgs e){   

  i++;
  label1.Text = i.ToString();
 }

Answer 4

Remove infinite loop ( while (true) ), but add 1 to the label1.Text :

private void ClickMebutton_Click(object sender, EventArgs e) {
  int value;

  if (int.TryParse(label1.Text, out value))
    label1.Text = (value + 1).ToString();
  else
    label1.Text = "1";
}

In case of C# 7.0+ you can put it terser, but less readable:

private void ClickMebutton_Click(object sender, EventArgs e) {
  label1.Text = (int.TryParse(label1.Text, out var value) ? value + 1 : 1).ToString();
}