Arduino Project: Button Switch

Arduino Button Switch

/*
Project: Button Switch
Programmer: Shahrulnizam Mat Rejab
Board: Arduino UNO
Last Modified: 18 February 2018
Website: http://shahrulnizam.com
*/

#define SW1           7
#define SW2           6
#define SW3           5
#define SW4           4
#define RELAY1        11
#define RELAY2        10
#define RELAY3        9
#define RELAY4        8

void setup()
{
  pinMode(SW1,INPUT_PULLUP);
  pinMode(SW2,INPUT_PULLUP);
  pinMode(SW3,INPUT_PULLUP);
  pinMode(SW4,INPUT_PULLUP);
  pinMode(RELAY1,OUTPUT);
  pinMode(RELAY2,OUTPUT);
  pinMode(RELAY3,OUTPUT);
  pinMode(RELAY4,OUTPUT);
  digitalWrite(RELAY1,LOW);
  digitalWrite(RELAY2,LOW);
  digitalWrite(RELAY3,LOW);
  digitalWrite(RELAY4,LOW);
}

void loop()
{
  if(digitalRead(SW1)==0)
  {
    digitalWrite(RELAY1,!digitalRead(RELAY1));
    delay(200);
    while(digitalRead(SW1)==0) continue;
  }

  if(digitalRead(SW2)==0)
  {
    digitalWrite(RELAY2,!digitalRead(RELAY2));
    delay(200);
    while(digitalRead(SW2)==0) continue;
  }

  if(digitalRead(SW3)==0)
  {
    digitalWrite(RELAY3,!digitalRead(RELAY3));
    delay(200);
    while(digitalRead(SW3)==0) continue;
  }

  if(digitalRead(SW4)==0)
  {
    digitalWrite(RELAY4,!digitalRead(RELAY4));
    delay(200);
    while(digitalRead(SW4)==0) continue;
  }      
}