TIL | Array Methods(Push, Pop, Shift, Unshift)


🚍 Array Methods
  • push - add to end
  • pop - remove from end
  • shift - remove from start
  • unshift - add to start
  • 👈 push() - add to end
    let movieLine = ["tom", "nance"];
    
    movieLine[2] = "pablo";
    movieLine; // ["tom", "nancy", "pablo"]
    
    movieLine.push('oliver');
    movieLine; // ["tom", "nancy", "pablo", "oliver"]
    
    movieLine.push('eva');
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva"]
    
    movieLine.push('harry', 'hermione');
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva", "harry", "hermione"]
    🤛 pop() - remove from end
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva", "harry", "hermione"]
    
    movieLine.pop() // "hermione"
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva", "harry"]
    
    
    let person = movieLine.pop();
    
    person; // "harry"
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva"]
    🏋️‍♂️ barbell example (stack & queue)
    let barbell = [];
    
    barbell.push(45);
    barbell.push(45);
    barbell.push(25);
    barbell.push(10);
    barbell.push(2.5);
    
    barbell; // [45, 45, 25, 10, 2.5]
    
    barbell.pop(); // 2.5
    barbell.pop(); // 10
    barbell.pop(); // 25
    barbell.pop(); // 45
    barbell.pop(); // 45
    🤜 shift() - remove from start
    movieLine; // ["tom", "nancy", "pablo", "oliver", "eva"]
    
    movieLine.shift(); // "tom"
    movieLine; // ["nancy", "pablo", "oliver", "eva"]
    
    let nextPatron = movieLine.shift();
    nextPatron; // "nancy"
    movieLine; ["pablo", "oliver", "eva"]
    
    movie.push('ryan');
    
    movieLine.shift(); // "pablo"
    movieLine.shift(); // "oliver"
    movieLine.shift(); // "eva"
    movieLine.shift(); // "ryan"
    
    movieLine.shift(); // undefined
    👉 unshift() - add to start
    movieLine.push('jerry', 'deniz', 'kevin', 'carly');
    movieLine; // ["jerry", "deniz", "kevin", "carly"]
    
    movieLine.unshift('VIP');
    movieLine; // ["VIP", "jerry", "deniz", "kevin", "carly"]
    
    movieLine.shift(); // "VIP"
    movieLine; // ["jerry", "deniz", "kevin", "carly"]