Arduino Uno - Send a serial message when button pressed.

Hi all. Sorry for my bad english, i speak french.

Today i wan't to send message when a button is pressed but if i use the sketch:

void setup() {
  // put your setup code here, to run once:
  pinMode(2, INPUT);

void loop() {
  // put your main code here, to run repeatedly
   if (digitalRead(2) == HIGH) {

In the serial i have 20-30x "1"

I want to have just one "1", what can i do plz ?

The change should be detected. That means a variable is needed to remember the previous change. This is the state change example :

Sorry that no one has answered your other question yet ( ).

Thank you for your answer !

For my first post, i have found the problem :)