一个用PHP编写的
源代码在线查看： dom-drag.js
/************************************************** * dom-drag.js * 09.25.2001 * www.youngpup.net ************************************************** * 10.28.2001 - fixed minor bug where events * sometimes fired off the handle, not the root. **************************************************/ var Drag = { obj : null, init : function(o, oRoot, minX, maxX, minY, maxY, bSwapHorzRef, bSwapVertRef, fXMapper, fYMapper) { o.onmousedown = Drag.start; o.hmode = bSwapHorzRef ? false : true ; o.vmode = bSwapVertRef ? false : true ; o.root = oRoot && oRoot != null ? oRoot : o ; if (o.hmode && isNaN(parseInt(o.root.style.left ))) o.root.style.left = "0px"; if (o.vmode && isNaN(parseInt(o.root.style.top ))) o.root.style.top = "0px"; if (!o.hmode && isNaN(parseInt(o.root.style.right ))) o.root.style.right = "0px"; if (!o.vmode && isNaN(parseInt(o.root.style.bottom))) o.root.style.bottom = "0px"; o.minX = typeof minX != 'undefined' ? minX : null; o.minY = typeof minY != 'undefined' ? minY : null; o.maxX = typeof maxX != 'undefined' ? maxX : null; o.maxY = typeof maxY != 'undefined' ? maxY : null; o.xMapper = fXMapper ? fXMapper : null; o.yMapper = fYMapper ? fYMapper : null; o.root.onDragStart = new Function(); o.root.onDragEnd = new Function(); o.root.onDrag = new Function(); }, start : function(e) { var o = Drag.obj = this; e = Drag.fixE(e); var y = parseInt(o.vmode ? o.root.style.top : o.root.style.bottom); var x = parseInt(o.hmode ? o.root.style.left : o.root.style.right ); o.root.onDragStart(x, y); o.lastMouseX = e.clientX; o.lastMouseY = e.clientY; if (o.hmode) { if (o.minX != null) o.minMouseX = e.clientX - x + o.minX; if (o.maxX != null) o.maxMouseX = o.minMouseX + o.maxX - o.minX; } else { if (o.minX != null) o.maxMouseX = -o.minX + e.clientX + x; if (o.maxX != null) o.minMouseX = -o.maxX + e.clientX + x; } if (o.vmode) { if (o.minY != null) o.minMouseY = e.clientY - y + o.minY; if (o.maxY != null) o.maxMouseY = o.minMouseY + o.maxY - o.minY; } else { if (o.minY != null) o.maxMouseY = -o.minY + e.clientY + y; if (o.maxY != null) o.minMouseY = -o.maxY + e.clientY + y; } document.onmousemove = Drag.drag; document.onmouseup = Drag.end; return false; }, drag : function(e) { e = Drag.fixE(e); var o = Drag.obj; var ey = e.clientY; var ex = e.clientX; var y = parseInt(o.vmode ? o.root.style.top : o.root.style.bottom); var x = parseInt(o.hmode ? o.root.style.left : o.root.style.right ); var nx, ny; if (o.minX != null) ex = o.hmode ? Math.max(ex, o.minMouseX) : Math.min(ex, o.maxMouseX); if (o.maxX != null) ex = o.hmode ? Math.min(ex, o.maxMouseX) : Math.max(ex, o.minMouseX); if (o.minY != null) ey = o.vmode ? Math.max(ey, o.minMouseY) : Math.min(ey, o.maxMouseY); if (o.maxY != null) ey = o.vmode ? Math.min(ey, o.maxMouseY) : Math.max(ey, o.minMouseY); nx = x + ((ex - o.lastMouseX) * (o.hmode ? 1 : -1)); ny = y + ((ey - o.lastMouseY) * (o.vmode ? 1 : -1)); if (o.xMapper) nx = o.xMapper(y) else if (o.yMapper) ny = o.yMapper(x) Drag.obj.root.style[o.hmode ? "left" : "right"] = nx + "px"; Drag.obj.root.style[o.vmode ? "top" : "bottom"] = ny + "px"; Drag.obj.lastMouseX = ex; Drag.obj.lastMouseY = ey; Drag.obj.root.onDrag(nx, ny); return false; }, end : function() { document.onmousemove = null; document.onmouseup = null; Drag.obj.root.onDragEnd( parseInt(Drag.obj.root.style[Drag.obj.hmode ? "left" : "right"]), parseInt(Drag.obj.root.style[Drag.obj.vmode ? "top" : "bottom"])); Drag.obj = null; }, fixE : function(e) { if (typeof e == 'undefined') e = window.event; if (typeof e.layerX == 'undefined') e.layerX = e.offsetX; if (typeof e.layerY == 'undefined') e.layerY = e.offsetY; return e; } };
