Is it possible to convert the following four anonymous jquery functions into one function that gets a parameter passed?
this is what I have...
dropZone.addEventListener("dragenter", this.dragEnter, false);
dropZone.addEventListener("dragover", this.dragOver, false);
dropZone.addEventListener("dragleave", this.dragLeave, false);
dropZone.addEventListener("drop", this.dragDrop, false);
...
this.dragOver = function(ev) {
ev.stopPropagation();
ev.preventDefault();
this.className = "dragover";
}
this.dragLeave = function(ev) {
ev.stopPropagation();
ev.preventDefault();
this.className = "dragleave";
}
this.dragEnter = function(ev) {
ev.stopPropagation();
ev.preventDefault();
this.className = "dragenter";
}
this.dragDrop = function(ev) {
ev.stopPropagation();
ev.preventDefault();
this.className = "dragdrop";
}
I'm looking for something functionally similar to...
dropZone.addEventListener("dragenter", dropEvent(this,"dragenter"), false);
dropZone.addEventListener("dragover", dropEvent(this,"dragOver"), false);
dropZone.addEventListener("dragleave", dropEvent(this,"dragLeave"), false);
dropZone.addEventListener("drop", dropEvent(this,"dragDrop"), false);
...
function dragEvent(ev, label) {
ev.stopPropagation();
ev.preventDefault();
this.className = label;
}
You can do that using a partially-applied function:
function dragEvent(that, label) {
return function(ev) {
ev.stopPropagation();
ev.preventDefault();
that.className = label;
}
}
You can read more about partial application in javascript here: http://benalman.com/news/2012/09/partial-application-in-javascript/
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