去
Here
使用向上和向下键
当我按下一个键时,红色框向下移动,暂停,然后移动其余部分.
如何删除暂停？
解决方法
你应该遵循keydown和keyup并使用间隔来更顺畅地移动球拍.
演示：http://jsfiddle.net/M7TKc/16/
var paddle = $("#paddle");
paddle.css({backgroundColor: "red",height:"100px",width:"25px",position: "absolute"});
var paddle_y = 0,moving = 0; /* added */
draw_paddle();
window.setInterval(function () { /* added */
if (moving != 0) {
paddle_y += moving;
draw_paddle();
}},100);
function move_down(){
moving = -10;
}
function move_up(){
moving = 10;
}
function draw_paddle(){
paddle.css({top: paddle_y+"px"});
}
$(document).keypress(function(e) {
if(e.which == 13) {
// stop on "ENTER"
moving = 0;
}
});
$(document).keydown(function(e){ /* changed */
if (e.keyCode == 38)
move_down();
else if (e.keyCode == 40)
move_up();
});
$(document).keyup(function(e){ /* added */
if (e.keyCode == 38 || e.keyCode == 40)
moving = 0;
});