Visual C# - Error 1 The name 'a' does not exist in the current context

Question

private void button6_Click(object sender, EventArgs e)
{  

     for (int i = 0; i < a.Length; i++)
     {
        MessageBox.Show(a[i]);
     }

 }

 public void button7_Click(object sender, EventArgs e)
 {
      string[] a = { textBox1.Text};
 }

Answer 1

a is a method variable; it only exists per call to button7_Click. I suspect you need to make it a *field:

     for (int i = 0; i < a.Length; i++)
    {
        MessageBox.Show(a[i]);
    }

}
private string[] a;
public void button7_Click(object sender, EventArgs e)
{
     a = new string[]{ textBox1.Text};
}

and then: choose a better name than a.

Answer 2

a is not in scope inside the button6 click.

You must declare it as a field, within that handler or pass it in within a custom eventargs.

You could do this also

 private void button6_Click(object sender, EventArgs e) {
        string[] a = { textBox1.Text};
        for (int i = 0; i < a.Length; i++)
        {
            MessageBox.Show(a[i]);
        }

    }

Answer 3

Because a is defined as a local variable for the button7_click function make it global over the form; define it on the variables of the form

Answer 4

you're calling "a.Length" in button6_Click but a is not defined in that method. if you need "a" in both methods you need to make it a class variable. but by the looks of this you could just as well get the contents of the textbox in method button6_Click.