JavaScript 更好的Javascript键盘导航

Posted 2021-05-20

function init(){
	currentpos = 0
	h1tags = document.body.getElementsByTagName("h3");
	setInterval("locator()",500)
}
function locator(){
	checkpos=0
	while(h1tags[checkpos+1]!=undefined){
		if(h1tags[checkpos].offsetTop>(window.pageYOffset-(window.innerHeight)+h1tags[checkpos].clientHeight)){
			currentpos = checkpos
			checkpos = -3
		}
		checkpos = checkpos+1;
	}
}	
function keycatch(){
	keypress = event.keyCode
	switch(keypress){
		case 37: // Left
			if(currentpos!=0){
				currentpos = currentpos-1;
				h1tags[currentpos].scrollIntoView();
			}
			return false
			break;
		case 39: // Right
			if(h1tags[currentpos+1]!=undefined){
				currentpos = currentpos+1;
				h1tags[currentpos].scrollIntoView();
			}
			return false
			break;
	}
}