基于JQuery的弹幕APP

今天闲着无聊，写了个弹幕APP，主要实现以下几个功能：

1.点击“弹幕发射”或回车可以输出弹幕到弹幕墙上。

2.弹幕的运行轨迹是从弹幕墙的最右边到最左边，Y轴的数值在弹幕墙的高度内随机，颜色HEX随机，速度随机。

3.右侧的表格可以储存弹幕内容以及弹幕的发射时间，越靠近现在的越靠前。

4.点击“清除弹幕”可以把弹幕墙内的所有弹幕清除掉，但不会影响到表格中的数据。

5.如果弹幕长度过长（我设置的是6个字符），则超过规定长度之外的弹幕内容都会由“...”代替，并放入表格中。但弹幕墙中的内容依然是完整的。

HTML代码：

<div class="frame">
  <div class="row">
    <div class="col-xs-8 col-sm-8 col-md-8 col-lg-8 danmu-box-frame">
      <div class="danmu-box">
      </div>
    </div>
    <div class="col-xs-4 col-sm-4 col-md-4 col-lg-4 danmu-table-frame">
      <table class="table .table-condensed danmu-table">
        <thead>
          <tr>
            <th>
              弹幕内容
            </th>
            <th>
              弹幕时间
            </th>
          </tr>
        </thead>
        <tbody>
        </tbody>
      </table>
    </div>
  </div>
  <div class="danmu-form">
    <form class="form-inline">
      <input type="text" class="form-control" placeholder="开始吐槽！">
      <button type="button" class="btn btn-primary shoot">
        发射弹幕！
      </button>
      <button type="button" class="btn btn-danger clear">
        清空弹幕
      </button>
    </form>
  </div>
</div>
<hr>
<footer>
  Designed By
  <a href="http://blog.csdn.net/alenhhy" target="_blank">
    Alen Hu
  </a>
</footer>

*使用了Bootstrap3框架。

JQuery部分：

$(document).ready(function() {
  $(".shoot").on("click", startDanmu);
  $("form").keypress(function(event) {
    if (event.keyCode === 13) {
      event.preventDefault();
      startDanmu();
    }
  });
  $(".clear").on("click", clearDanmu);
});

//get random number in certain range
function RandomNum(Min, Max) {
  var Range = Max - Min;
  var Rand = Math.random();
  var num = Min + Math.round(Rand * Range);
  return num;
}

//time number add 0 before if <10
function plusZero(x) {
  if (x < 10) {
    x = "0" + x;
  } else {
    x = x;
  }
  return x;
}

//start danmu
function startDanmu() {

  var message = $("input");
  var messageVal = message.val();
  var danmuMessage = "<span class='danmu-message'>" + messageVal + "</span>";

  //get random color HEX
  //u can also save the colors u want by array
  var color = RandomNum(100000, 999999);

  //get random danmu speed
  var speed = RandomNum(10000, 20000);

  //get random position Y
  //danmu box height is 450, we set the danmu position Y max 400 in case it blocks the subtitle
  var positionY = RandomNum(50, 400);

  if (messageVal.length > 0) {
    //insert danmu message into danmu box
    $(".danmu-box").prepend(danmuMessage);

    //have to use first() cuz we prepend the message, u can try what's gonna happen if no first()
    //set it's style
    $(".danmu-message").first().css({
      "right": "0",
      "top": positionY,
      "color": "#" + color
    });

    //set it's animation
    //from right 0 to left 0
    //hide it after move
    $(".danmu-message").first().animate({
      left: '0px',
    },
    speed,
    function() {
      $(this).fadeOut();
    });
    //get danmu time
    var time = new Date();
    var month = time.getMonth() + 1;
    var day = time.getDay();
    var hour = time.getHours();
    var minute = time.getMinutes();
    var danmuTime = plusZero(month) + "-" + plusZero(day) + " " + plusZero(hour) + ":" + plusZero(minute);

    //insert danmu message to table
    if (messageVal.length > 6) {
      messageVal = messageVal.substring(0, 6) + "...";
    }
    var messageToTable = "<tr><td>" + messageVal + "</td><td>" + danmuTime + "</td></tr>";
    $(".danmu-table > tbody").prepend(messageToTable);

  } else {}

  //empty the input
  message.val("");
}

//clear danmu box
function clearDanmu() {
  $(".danmu-box").html("");
}

DEMO在这儿，欢迎来FORK： Danmu APP。