無法在Typescript中移除EventListener
我正在嘗試刪除打字稿中的事件偵聽器。我在 if 語句中新增事件監聽器。在 else 語句中，我試圖刪除這些事件監聽器，但由於某種原因它沒有刪除它們。
僅供參考：我有一個按鈕，可以在其中設定布林值（movePick）。如果這是真的那麼我希望能夠移動我的物件。這就是建立事件偵聽器的地方。如果我再次單擊該按鈕，我將無法再移動該物件。這就是我嘗試刪除事件偵聽器的原因。
public moveObject(movePick: boolean, raycaster: THREE.Raycaster): void {
const plane = new THREE.Plane();
const pNormal = new THREE.Vector3(0, 1, 0); // plane's normal
const planeIntersect = new THREE.Vector3(); // point of intersection with the plane
const pIntersect = new THREE.Vector3(); // point of intersection with an object (plane's point)
const shift = new THREE.Vector3(); // distance between position of an object and points of intersection with the object
let isDragging = false;
let dragObject: any;
// events
const pointermove = (event: PointerEvent) => {
const rect = this.canvas.getBoundingClientRect();
const x = event.clientX - rect.left
const y = event.clientY - rect.top
const pickPosition = { x: 0, y: 0 };
pickPosition.x = (x / this.canvas.clientWidth) * 2 - 1;
pickPosition.y = (y / this.canvas.clientHeight) * -2 + 1;
raycaster.setFromCamera(pickPosition, this.camera);
// console.log("movePICK IN POINTERMOVE",movePick)
if (isDragging) {
raycaster.ray.intersectPlane(plane, planeIntersect);
dragObject.position.addVectors(planeIntersect, shift);
}
}
const mousedown = () => {
const intersects = raycaster.intersectObjects(this.scene.children);
for (let i = 0; i < this.mesharr.length; i++) {
if (intersects[0].object.name == this.mesharr[i].name && intersects[0].object.name != "Rail") {
pIntersect.copy(intersects[0].point);
plane.setFromNormalAndCoplanarPoint(pNormal, pIntersect);
shift.subVectors(intersects[0].object.position, intersects[0].point);
isDragging = true;
dragObject = intersects[0].object;
}
}
}
const pointerup = () => {
isDragging = false;
dragObject = null;
}
**if (movePick) {
document.addEventListener("pointermove", pointermove);
document.addEventListener("mousedown", mousedown);
document.addEventListener("pointerup", pointerup);
} else {
document.removeEventListener("pointermove", pointermove);
document.removeEventListener("mousedown", mousedown);
document.removeEventListener("pointerup", pointerup);
}**
}
如果我在新增事件列表的同一個 if 語句中刪除事件列表，它們就會被刪除。但如果再次按一下該按鈕並進入 else 語句，則無法刪除它們。我也在 stackoverflow 中嘗試了幾種解決方案，但都不起作用。
