Read number from text file and display it in a textbox in C# -

i have text file (abcd.txt) contains number (456700010234) in it. abcd.txt file contains number (456700010234). nothing else.

i want display number in 1 of text boxes in c# form. prefer not use button. textbox in form/usercontrol.

if anytime want change number, update text file (abcd.txt) new number , thus, new number appear in textbox automatically each time open form. way, won't have re-program software whenever number changes. want update .txt file new number if number changes.

you first have create handler form_load event, this:

private void form1_load(object sender, system.eventargs e) {  } 

then need set text property of text box result of reading of data (one line) text file, this:

private void form1_load(object sender, system.eventargs e) {     yourtextbox.text = file.readalltext("abcd.txt"); } 

now whenever form loads go out , read contents of file , display number in text file user.