keyPressed.js

function keyPressed(e){
  	if(!game && guess>0){
			var keyPressed = String.fromCharCode(e.keyCode)//获得按下的键的值
			,	keyPressedIndex;
			keyPressed = keyPressed.toLowerCase();
			lettersGuessed.push(keyPressed);
			keyPressedIndex = letters.indexOf(keyPressed);
			if(keyPressedIndex >= 0){
				guess = guess - 1;
				if(keyPressedIndex === index) {
					game = true;//用户获胜，game的值为true
					LowerOrHigher = "You win!";
					letterToGArray.push(letterToGuess);
				} else {
					if(guess > 0) {
						if(keyPressedIndex > index) {
							LowerOrHigher = "Lower";
						}
						if(keyPressedIndex < index) {
							LowerOrHigher = "Higher";
						}
					} 
					if(guess == 0 && game == false) {
						letterToGArray.push(letterToGuess);
						LowerOrHigher = "game over!";
					}
				}
			} else{
				LowerOrHigher = "That is not a letter";
				if(guess == 0) {
					letterToGArray.push(letterToGuess);
				}
			}
		}
		canv.height = "300";//重新绘制
		drawScreen();
	}