如何在第一次单击时执行操作并在第二次单击时执行另一个操作

Question

My goal is to move a div element to the right side of the page on the first click and move it back to the left if I click it again and so on. How can I do this in javascript?

Answer 1

As enhzfelp said in their comment, the best solution would be to create a css class which moves your element to the right side of the page and to add / remove it with javascript.

If your goal is actually to perform one action and on next event call perform another, you can simply change a variable whenever the event is called.

Example code:

let right = false;

someElement.on('click', () => {
  right = !right;

  if (right) moveRight();
  else moveLeft();
});

function moveRight() { ... }
function moveLeft() { ... }

Answer 2

You can also do this

<script>
var clickCount = 0;
function checkClick() {
  if ( clickCount % 2 == 0 ) {
       alert("first click");
  } else {
      alert("Second click");
  }

  clickCount++
}
</script>

<button onclick="checkClick()">Click me</button>

Answer 3

Hmm, my english is kinda weak so I'll try my best to explain.

Let's assume we have a div with id moveable

<div id="moveable"></div>

And we have button

<button id="move">Move</div>

And our goal is to move the div to the right in the first click, and in the second click we will move it back to the right.

var div = document.getElementById("moveable");
var button = document.getElementById("move"):

button.addEventListener("click", function() {
if (div.getAttribute("data-moved") && div.getAttribute("data-moved") == true){
div.setAttribute("data-moved", "false");
div.style.float = "left";
} else {
div.setAtteibute("data-moved", "true")
div.style.float = "right"
}
})

Answer 4

So, as I understood, you want to make so on click, the div element move to the opositive direction of left or right.

You can make this with an event listener, that listens to the click event and execute whatever you want on every click.

document.addEventListener('click', function(event) {
  // your code that executes on every click
});

This event listener listens the click on all your webpage, so if you want to only listen the click when the use click your div, you need to get the div. There are several ways, but I recomend you to add an id to the div.

<div id="iAmYourElement"></div>

And then get the element in JavaScript

const element = document.getElementById("iAmYourElement");
element.addEventListener('click', function(event) {
  // your code that executes on every click
});

Now that we have the way to deal with the click event, let's talk about the code that goes inside the listener.

One way to do this is creating two CSS classes, one is your div on the left and another whe div on your right. So, if we need the element to be on the right, we add the right-class, and if we need the div to be to the left, we add left-class and remove right-class.

Final javascript code will looks like that:

const element = document.getElementById("iAmYourElement");

let isDivOnLeft = true;
element.addEventListener('click', function (event) { // executes if you click on the div
  isDivOnLeft = !isDivOnLeft // We negate the value of isDivOnLeft, so if it was true, it will now be false and vice versa.
  if (isDivOnLeft) {
    elementToRight()
  } else {
    elementToLeft()
  }
});

function elementToRight() {
  element.classList.remove("left-class")
  element.classList.add("right-class")
}

function elementToLeft() {
  element.classList.remove("right-class")
  element.classList.add("left-class")
}