javascript - 按下按钮时让烟花发射

Question

我一直在尝试弄清楚如何在单击按钮时发射烟花。我可以让音频播放得很好，但不是烟花。我不确定是否应该在不同的区域添加 EventListener，或者我是否需要尝试不同的方法。

我试过添加一个 EventListener，向现有的 EventListner 添加点击，并向启动器 CSS 和按钮添加一个类.

function play(){
       var audio = document.getElementById("audio");
       audio.play();
      };

// Fireworks
document.addEventListener("DOMContentLoaded", function() {
  var num_launchers = 12;
  var num_flares = 20;
  var flare_colours = ['#f22613', '#ffffff', '#22a7f0', '#00b5cc', '#f3f1ef', '#d91e18'];
  var cssIdx = document.styleSheets.length - 1;

  function myRandom(from, to)
  {
    return from + Math.floor(Math.random() * (to-from));
  }

  var keyframes_template = "from { left: LEFTFROM%; top: 380px; width: 6px; height: 12px; }\n"
      + "33% { left: LEFTTOP%; top: TOPTOPpx; width: 0; height: 0; }\n"
      + " to { left: LEFTEND%; top: BOTBOTpx; width: 0; height: 0; }";

  for(var i=0; i < num_launchers; i++) {
    leftfrom = myRandom(15, 85);
    lefttop = myRandom(30, 70);
    toptop = myRandom(20, 200);
    leftend = lefttop + (lefttop-leftfrom)/2;
    botbot = toptop + 100;

    csscode = keyframes_template;
    csscode = csscode.replace(/LEFTFROM/, leftfrom);
    csscode = csscode.replace(/LEFTTOP/, lefttop);
    csscode = csscode.replace(/TOPTOP/, toptop);
    csscode = csscode.replace(/LEFTEND/, leftend);
    csscode = csscode.replace(/BOTBOT/, botbot);

    try {
      csscode2 = "@-webkit-keyframes flight_" + i + " {\n" + csscode + "\n}";
      document.styleSheets[cssIdx].insertRule(csscode2, 0);
    } catch(e) { }

    try { 
      csscode2 = "@-moz-keyframes flight_" + i + " {\n" + csscode + "\n}";
      document.styleSheets[cssIdx].insertRule(csscode2, 0);
    } catch(e) { }
  }

  for(var i=0; i < num_launchers; i++) {
    var rand = myRandom(0, flare_colours.length - 1);
    var rand_colour = flare_colours[rand];
    var launch_delay = myRandom(0,100) / 10;

    csscode = ".launcher:nth-child(" + num_launchers + "n+" + i + ") {\n"
      + "  -webkit-animation-name: flight_" + i + ";\n"
      + "  -webkit-animation-delay: " + launch_delay + "s;\n"
      + "  -moz-animation-name: flight_" + i + ";\n"
      + "  -moz-animation-delay: " + launch_delay + "s;\n"
      + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);

    csscode = ".launcher:nth-child(" + num_launchers + "n+" + i + ") div {"
      + "  border-color: " + rand_colour + ";\n"
      + "  -webkit-animation-delay: " + launch_delay + "s;\n"
      + "  -moz-animation-delay: " + launch_delay + "s;\n"
      + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);
  }

  for(var i=0; i < num_flares; i++) {
    csscode = ".launcher div:nth-child(" + num_flares + "n+" + i + ") {\n"
    + "  -webkit-transform: rotate(" + (i * 360/num_flares) + "deg);\n"
    + "  -moz-transform: rotate(" + (i * 360/num_flares) + "deg);\n"
    + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);
  }

  for(var i=0; i < num_launchers; i++) {
    var newdiv = document.createElement("div");
    newdiv.className = "launcher";
    for(var j=0; j < num_flares; j++) {
      newdiv.appendChild(document.createElement("div"));
    }
    document.getElementById("stage").appendChild(newdiv);
  }
}, false);

我希望在单击按钮时开始播放音乐和烟花。如果您需要 CSS 或 HTML，我也可以添加。

Answer 1

在这个 block 内调用烟花

document.getElementById("btn").addEventListener("click", function(){place firework});

document.getElementById("btn").addEventListener("click", function(){

  // Fireworks
document.addEventListener("DOMContentLoaded", function() {
  var num_launchers = 12;
  var num_flares = 20;
  var flare_colours = ['#f22613', '#ffffff', '#22a7f0', '#00b5cc', '#f3f1ef', '#d91e18'];
  var cssIdx = document.styleSheets.length - 1;

  function myRandom(from, to)
  {
    return from + Math.floor(Math.random() * (to-from));
  }

  var keyframes_template = "from { left: LEFTFROM%; top: 380px; width: 6px; height: 12px; }\n"
      + "33% { left: LEFTTOP%; top: TOPTOPpx; width: 0; height: 0; }\n"
      + " to { left: LEFTEND%; top: BOTBOTpx; width: 0; height: 0; }";

  for(var i=0; i < num_launchers; i++) {
    leftfrom = myRandom(15, 85);
    lefttop = myRandom(30, 70);
    toptop = myRandom(20, 200);
    leftend = lefttop + (lefttop-leftfrom)/2;
    botbot = toptop + 100;

    csscode = keyframes_template;
    csscode = csscode.replace(/LEFTFROM/, leftfrom);
    csscode = csscode.replace(/LEFTTOP/, lefttop);
    csscode = csscode.replace(/TOPTOP/, toptop);
    csscode = csscode.replace(/LEFTEND/, leftend);
    csscode = csscode.replace(/BOTBOT/, botbot);

    try {
      csscode2 = "@-webkit-keyframes flight_" + i + " {\n" + csscode + "\n}";
      document.styleSheets[cssIdx].insertRule(csscode2, 0);
    } catch(e) { }

    try { 
      csscode2 = "@-moz-keyframes flight_" + i + " {\n" + csscode + "\n}";
      document.styleSheets[cssIdx].insertRule(csscode2, 0);
    } catch(e) { }
  }

  for(var i=0; i < num_launchers; i++) {
    var rand = myRandom(0, flare_colours.length - 1);
    var rand_colour = flare_colours[rand];
    var launch_delay = myRandom(0,100) / 10;

    csscode = ".launcher:nth-child(" + num_launchers + "n+" + i + ") {\n"
      + "  -webkit-animation-name: flight_" + i + ";\n"
      + "  -webkit-animation-delay: " + launch_delay + "s;\n"
      + "  -moz-animation-name: flight_" + i + ";\n"
      + "  -moz-animation-delay: " + launch_delay + "s;\n"
      + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);

    csscode = ".launcher:nth-child(" + num_launchers + "n+" + i + ") div {"
      + "  border-color: " + rand_colour + ";\n"
      + "  -webkit-animation-delay: " + launch_delay + "s;\n"
      + "  -moz-animation-delay: " + launch_delay + "s;\n"
      + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);
  }

  for(var i=0; i < num_flares; i++) {
    csscode = ".launcher div:nth-child(" + num_flares + "n+" + i + ") {\n"
    + "  -webkit-transform: rotate(" + (i * 360/num_flares) + "deg);\n"
    + "  -moz-transform: rotate(" + (i * 360/num_flares) + "deg);\n"
    + "}";
    document.styleSheets[cssIdx].insertRule(csscode, 0);
  }

  for(var i=0; i < num_launchers; i++) {
    var newdiv = document.createElement("div");
    newdiv.className = "launcher";
    for(var j=0; j < num_flares; j++) {
      newdiv.appendChild(document.createElement("div"));
    }
    document.getElementById("stage").appendChild(newdiv);
  }
}, false);

});