SendKeys.Send("hello"); continuously sending string how can i send only once

Question

This code is continuously sending a string. I need a solution which can send the supplied string only once by clicking a button in the window which has the focus.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        SendKeys.Send("This is a test...");
    }
}

How many times does it send keys with this code? Is this the only code? Are you sure this is not interfering with some other logic? — Chetan, Jun 20 '17 at 19:26
@rory.ap That code seems to repro the "problem" for me. Does it not for you? — Rufus L, Jun 20 '17 at 19:30
I also found this and it was helpful: https://stackoverflow.com/questions/3047375/simulating-key-press-c-sharp — Fredy, Sep 01 '22 at 18:15

Rufus L · Answer 1 · 2017-06-20T19:35:02.717

1

The issue seems to be the fact that the button1 control has the focus, and when you send certain keys to it (like the space in your example), it triggers the Click event, and you end up in an infinite loop.

Try adding a TextBox to your form and then set focus to that first (or if you already know the thing that should receive the text, ensure that it has the focus before you call SendKeys):

private void button1_Click(object sender, EventArgs e)
{
    textBox1.Focus();
    SendKeys.Send("This is a test...");
}

edited Jun 20 '17 at 19:35

answered Jun 20 '17 at 19:32

Rufus L

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Space can trigger the click event on buttons (I verified this on a focused button in one of my winforms applications) – Blake Thingstad Jun 20 '17 at 19:33

SendKeys.Send("hello"); continuously sending string how can i send only once

1 Answers1