挺好的浮动广告，用于初学的

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; 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();