JavaScript產生的動態下雨背景效果實作方法_javascript技巧

本文實例講述了JavaScript產生的動態下雨背景效果實作方法。分享給大家供大家參考。具體實作方法如下：

複製程式碼 程式碼如下:

"); }
  else {
    document.write("

    document.write("absolute; Z-INDEX: " i "; VISIBILITY: ");
    document.write("visible; TOP: 15px; LEFT: 15px;">");
    document.write(",.");  }
}

function initRain() {
  a = 6;
  r[i] = 1;
  sn = Math.sin(a);
  cs = Math.cos(a);
  cx[i] = Math.random() * doc_width 1;
  cy[i] = Math.random() * doc_height 1;
  x[i] = r[i] * sn cx[i];
  y[i] = cy[i];
}

function raindropIE() {
  for (i = 0; i      updateRain();
     if ((x[i] = (doc_width - 20)) || (y[i] >= (doc_height - 20))) {
         makeRain();
         doc_width = document.body.clientWidth;
         doc_height = document.body.clientHeight; }
     document.all["dot" i].style.pixelTop = y[i];
     document.all["dot" i].style.pixelLeft = x[i]; }
  setTimeout("raindropIE()", speed);
}
function updateRain() {
  r[i] = 10;
  x[i] = r[i] * sn cx[i];
  y[i] = r[i] * cs cy[i];
}
function makeRain() {
  r[i] = 1;
  cx[i] = Math.random() * doc_width 1;
  cy[i] = 1;
  x[i] = r[i] * sn cx[i];
  y[i] = r[i] * cs cy[i];
}
raindropIE();

希望本文所述對大家的javascript程式設計有所幫助。