这是因为DOCTYPE是不能使用document.body的,一定要改成document.documentElement,还有就是不要忘记了"px",这很重要,浏览器都是以像素运算的。
- var xPos = 300;
- var yPos = 200;
- var step = 1;
- var delay = 30;
- var height = 0;
- var Hoffset = 0;
- var Woffset = 0;
- var yon = 0;
- var xon = 0;
- var pause = true;
- var interval;
- var img1 = document.getElementById("img1");
- img1.style.top = yPos;
- function changePos()
- {
- width = document.body.clientWidth;
- height = document.body.clientHeight;
- Hoffset = img1.offsetHeight;
- Woffset = img1.offsetWidth;
- img1.style.left = xPos + document.body.scrollLeft;
- img1.style.top = yPos + document.body.scrollTop;
- if (yon)
- {yPos = yPos + step;}
- else
- {yPos = yPos - step;}
- if (yPos < 0)
- {yon = 1;yPos = 0;}
- if (yPos >= (height - Hoffset))
- {yon = 0;yPos = (height - Hoffset);}
- if (xon)
- {xPos = xPos + step;}
- else
- {xPos = xPos - step;}
- if (xPos < 0)
- {xon = 1;xPos = 0;}
- if (xPos >= (width - Woffset))
- {xon = 0;xPos = (width - Woffset); }
- }
- function start()
- {
- img1.visibility = "visible";
- interval = setInterval('changePos()', delay);
- }
- function pause_resume()
- {
- if(pause)
- {
- clearInterval(interval);
- pause = false;}
- else
- {
- interval = setInterval('changePos()',delay);
- pause = true;
- }
- }
- start();
- var xPos = 300;
- var yPos = 200;
- var step = 1;
- var delay = 30;
- var height = 0;
- var Hoffset = 0;
- var Woffset = 0;
- var yon = 0;
- var xon = 0;
- var pause = true;
- var interval;
- var img1 = document.getElementById("img1");
- img1.style.top = yPos;
- function changePos()
- {
- width = document.documentElement.clientWidth;
- height = document.documentElement.clientHeight;
- Hoffset = img1.offsetHeight;
- Woffset = img1.offsetWidth;
- img1.style.left = xPos + document.documentElement.scrollLeft + "px";
- img1.style.top = yPos + document.documentElement.scrollTop + "px";
- if (yon)
- {yPos = yPos + step;}
- else
- {yPos = yPos - step;}
- if (yPos < 0)
- {yon = 1;yPos = 0;}
- if (yPos >= (height - Hoffset))
- {yon = 0;yPos = (height - Hoffset);}
- if (xon)
- {xPos = xPos + step;}
- else
- {xPos = xPos - step;}
- if (xPos < 0)
- {xon = 1;xPos = 0;}
- if (xPos >= (width - Woffset))
- {xon = 0;xPos = (width - Woffset); }
- }
- function start()
- {
- img1.visibility = "visible";
- interval = setInterval('changePos()', delay);
- }
- function pause_resume()
- {
- if(pause)
- {
- clearInterval(interval);
- pause = false;}
- else
- {
- interval = setInterval('changePos()',delay);
- pause = true;
- }
- }
- start();
或者你也可以直接把
- <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
改成:
- <!DOCTYPE>
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