基于Marquee.js插件实现的跑马灯效果示例

/****************************************************************
- Marquee.js
- 参数：
- ID：滚动对象（必须）
- Direction：滚动方向（"top": 0, "up": 0, "bottom": 1, "down": 1, "left": 2, "right": 3）
- Step：步伐
- Width：宽度
- Height：高度
- Timer：影响步伐滚动速度
- DelayTime：延时时间
- WaitTime：初始化时的等待时间
- ScrollStep：卷页步伐
*****************************************************************/
function Marquee(obt) {
  if (obt == null || obt == "") {
    return;
  }
  this.ID = document.getElementById(obt.ID);
  if (!this.ID) {
    alert("初始化错误\r\n请检查标签id设置是否正确!");
    this.id = -1;
    return;
  }
  this.Direction = this.Width = this.Height = this.DelayTime = this.WaitTime = this.CTL = this.StartID = this.Stop = this.MouseOver = 0;
  this.Step = 1;
  this.Timer = 30;
  this.DirectionArray = { "top": 0, "up": 0, "bottom": 1, "down": 1, "left": 2, "right": 3 };
  if (typeof obt.Direction == "number" && obt.Direction) this.Direction = obt.Direction;
  if (typeof obt.Direction == "string" && obt.Direction) this.Direction = this.DirectionArray[obt.Direction.toString().toLowerCase()];
  if (typeof obt.Step == "number" && obt.Step) this.Step = obt.Step;
  if (typeof obt.Width == "number" && obt.Width) this.Width = obt.Width;
  if (typeof obt.Height == "number" && obt.Height) this.Height = obt.Height;
  if (typeof obt.Timer == "number" && obt.Timer) this.Timer = obt.Timer;
  if (typeof obt.DelayTime == "number" && obt.DelayTime) this.DelayTime = obt.DelayTime;
  if (typeof obt.WaitTime == "number" && obt.WaitTime) this.WaitTime = obt.WaitTime;
  if (typeof obt.ScrollStep == "number" && obt.ScrollStep) this.ScrollStep = obt.ScrollStep;
  this.ID.style.overflow = this.ID.style.overflowX = this.ID.style.overflowY = "hidden";
  this.ID.noWrap = true;
  this.IsNotOpera = (navigator.userAgent.toLowerCase().indexOf("opera") == -1);
  this.Start();
}
Marquee.prototype.Start = function() {
  if (this.ID == -1) return;
  if (this.Width == 0) this.Width = parseInt(this.ID.style.width);
  if (this.Height == 0) this.Height = parseInt(this.ID.style.height);
  if (this.Timer < 20) this.Timer = 20;
  if (this.WaitTime < 800) this.WaitTime = 800;
  this.HalfWidth = Math.round(this.Width / 2);
  this.HalfHeight = Math.round(this.Height / 2);
  this.BakStep = this.Step;
  this.ID.style.width = this.Width + "px";
  this.ID.style.height = this.Height + "px";
  if (typeof this.ScrollStep != "number") this.ScrollStep = this.Direction > 1 ? this.Width : this.Height;
  var templateLeft = "<table cellspacing='0' cellpadding='0' style='border-collapse:collapse;display:inline;'><tr><td noWrap=true style='white-space: nowrap;word-break:keep-all;'>MSCLASS_TEMP_HTML</td><td noWrap=true style='white-space: nowrap;word-break:keep-all;'>MSCLASS_TEMP_HTML</td></tr></table>";
  var templateTop = "<table cellspacing='0' cellpadding='0' style='border-collapse:collapse;'><tr><td>MSCLASS_TEMP_HTML</td></tr><tr><td>MSCLASS_TEMP_HTML</td></tr></table>";
  var msobj = this;
  msobj.tempHTML = msobj.ID.innerHTML;
  if (msobj.Direction <= 1) {
    msobj.ID.innerHTML = templateTop.replace(/MSCLASS_TEMP_HTML/g, msobj.ID.innerHTML);
  }
  else {
    if (msobj.ScrollStep == 0 && msobj.DelayTime == 0) {
      msobj.ID.innerHTML += msobj.ID.innerHTML;
    }
    else {
      msobj.ID.innerHTML = templateLeft.replace(/MSCLASS_TEMP_HTML/g, msobj.ID.innerHTML);
    }
  }
  var timer = this.Timer;
  var delaytime = this.DelayTime;
  var waittime = this.WaitTime;
  msobj.StartID = function() { msobj.Scroll() }
  msobj.Continue = function() {
    if (msobj.MouseOver == 1) {
      setTimeout(msobj.Continue, delaytime);
    }
    else {
      clearInterval(msobj.TimerID);
      msobj.CTL = msobj.Stop = 0;
      msobj.TimerID = setInterval(msobj.StartID, timer);
    }
  }
  msobj.Pause = function() {
    msobj.Stop = 1;
    clearInterval(msobj.TimerID);
    setTimeout(msobj.Continue, delaytime);
  }
  msobj.Begin = function() {
    msobj.ClientScroll = msobj.Direction > 1 ? msobj.ID.scrollWidth / 2 : msobj.ID.scrollHeight / 2;
    if ((msobj.Direction <= 1 && msobj.ClientScroll <= msobj.Height + msobj.Step) || (msobj.Direction > 1 && msobj.ClientScroll <= msobj.Width + msobj.Step)) {
      msobj.ID.innerHTML = msobj.tempHTML;
      delete (msobj.tempHTML);
      return;
    }
    delete (msobj.tempHTML);
    msobj.TimerID = setInterval(msobj.StartID, timer);
    if (msobj.ScrollStep < 0) return;
    msobj.ID.onmousemove = function(event) {
      if (msobj.ScrollStep == 0 && msobj.Direction > 1) {
        var event = event || window.event;
        if (window.event) {
          if (msobj.IsNotOpera) {
            msobj.EventLeft = event.srcElement.id == msobj.ID.id ? event.offsetX - msobj.ID.scrollLeft : event.srcElement.offsetLeft - msobj.ID.scrollLeft + event.offsetX;
          }
          else {
            msobj.ScrollStep = null;
            return;
          }
        }
        else {
          msobj.EventLeft = event.layerX - msobj.ID.scrollLeft;
        }
        msobj.Direction = msobj.EventLeft > msobj.HalfWidth ? 3 : 2;
        msobj.AbsCenter = Math.abs(msobj.HalfWidth - msobj.EventLeft);
        msobj.Step = Math.round(msobj.AbsCenter * (msobj.BakStep * 2) / msobj.HalfWidth);
      }
    }
    msobj.ID.onmouseover = function() {
      if (msobj.ScrollStep == 0) return;
      msobj.MouseOver = 1;
      clearInterval(msobj.TimerID);
    }
    msobj.ID.onmouseout = function() {
      if (msobj.ScrollStep == 0) {
        if (msobj.Step == 0) msobj.Step = 1;
        return;
      }
      msobj.MouseOver = 0;
      if (msobj.Stop == 0) {
        clearInterval(msobj.TimerID);
        msobj.TimerID = setInterval(msobj.StartID, timer);
      }
    }
  }
  setTimeout(msobj.Begin, waittime);
}
Marquee.prototype.Scroll = function() {
  switch (this.Direction) {
    case 0:
      this.CTL += this.Step;
      if (this.CTL >= this.ScrollStep && this.DelayTime > 0) {
        this.ID.scrollTop += this.ScrollStep + this.Step - this.CTL;
        this.Pause();
        return;
      }
      else {
        if (this.ID.scrollTop >= this.ClientScroll) {
          this.ID.scrollTop -= this.ClientScroll;
        }
        this.ID.scrollTop += this.Step;
      }
      break;
    case 1:
      this.CTL += this.Step;
      if (this.CTL >= this.ScrollStep && this.DelayTime > 0) {
        this.ID.scrollTop -= this.ScrollStep + this.Step - this.CTL;
        this.Pause();
        return;
      }
      else {
        if (this.ID.scrollTop <= 0) {
          this.ID.scrollTop += this.ClientScroll;
        }
        this.ID.scrollTop -= this.Step;
      }
      break;
    case 2:
      this.CTL += this.Step;
      if (this.CTL >= this.ScrollStep && this.DelayTime > 0) {
        this.ID.scrollLeft += this.ScrollStep + this.Step - this.CTL;
        this.Pause();
        return;
      }
      else {
        if (this.ID.scrollLeft >= this.ClientScroll) {
          this.ID.scrollLeft -= this.ClientScroll;
        }
        this.ID.scrollLeft += this.Step;
      }
      break;
    case 3:
      this.CTL += this.Step;
      if (this.CTL >= this.ScrollStep && this.DelayTime > 0) {
        this.ID.scrollLeft -= this.ScrollStep + this.Step - this.CTL;
        this.Pause();
        return;
      }
      else {
        if (this.ID.scrollLeft <= 0) {
          this.ID.scrollLeft += this.ClientScroll;
        }
        this.ID.scrollLeft -= this.Step;
      }
      break;
  }
}

window.onload = function() {
  new Marquee({ ID: "scrollNews", Direction: "top", Step: 2, Width: 0, Height: 80, Timer: 50, DelayTime: 1000, WaitTime: 1000, ScrollStep: 80 });
}