HTMLElement.offsetTop - Web APIs
the htmlelement.offsettop read-only property returns the distance of the current element relative to the top of the offsetparent node.
... syntax toppos = element.offsettop; parameters toppos is the number of pixels from the top of the closest relatively positioned parent element.
... example var d = document.getelementbyid("div1"); var toppos = d.offsettop; if (toppos > 10) { // object is offset more // than 10 pixels from its parent } specification specification status comment css object model (cssom) view modulethe definition of 'offsettop' in that specification.
... desktopmobilechromeedgefirefoxinternet exploreroperasafariandroid webviewchrome for androidfirefox for androidopera for androidsafari on iossamsung internetoffsettopchrome full support 1edge full support 12firefox full support 1ie full support 8opera full support 8safari full support 3webview a...

VisualViewport.offsetTop - Web APIs
the offsettop read-only property of the visualviewport interface returns the offset of the top edge of the visual viewport from the top edge of the layout viewport in css pixels.
... syntax var offsettop = visualviewport.offsettop value a double.
... specifications specification status comment visual viewport apithe definition of 'offsettop' in that specification.

HTMLElement.offsetLeft - Web APIs
for block-level elements, offsettop, offsetleft, offsetwidth, and offsetheight describe the border box of an element relative to the offsetparent.
... however, for inline-level elements (such as span) that can wrap from one line to the next, offsettop and offsetleft describe the positions of the first border box (use element.getclientrects() to get its width and height), while offsetwidth and offsetheight describe the dimensions of the bounding border box (use element.getboundingclientrect() to get its position).
... therefore, a box with the left, top, width and height of offsetleft, offsettop, offsetwidth and offsetheight will not be a bounding box for a span with wrapped text.
... span that wraps within this div.</span> </div> <div id="box" style="position: absolute; border-color: red; border-width: 1; border-style: solid; z-index: 10"> </div> <script type="text/javascript"> var box = document.getelementbyid("box"); var longspan = document.getelementbyid("longspan"); box.style.left = longspan.offsetleft + document.body.scrollleft + "px"; box.style.top = longspan.offsettop + document.body.scrolltop + "px"; box.style.width = longspan.offsetwidth + "px"; box.style.height = longspan.offsetheight + "px"; </script> specification specification status comment css object model (cssom) view modulethe definition of 'offsetleft' in that specification.

Color picker tool - CSS: Cascading Style Sheets
bind(this)); this.node.appendchild(button); }; /*************************************************************************/ // updates properties of ui elements /*************************************************************************/ colorpicker.prototype.updatecolor = function updatecolor(e) { var x = e.pagex - this.picking_area.offsetleft; var y = e.pagey - this.picking_area.offsettop; var picker_offset = 5; // width and height should be the same var size = this.picking_area.clientwidth; if (x > size) x = size; if (y > size) y = size; if (x < 0) x = 0; if (y < 0) y = 0; var value = 100 - (y * 100 / size) | 0; var saturation = x * 100 / size | 0; if (this.picker_mode === 'hsv') this.color.sethsv(this.color.hue, saturation, value); if (this.picker_mo...
... = 1; else if (axis === 'height') action = -1; else axis = 'both'; handle.classname = 'resize-handle'; handle.setattribute('data-resize', axis); handle.addeventlistener('mousedown', resizestart); elem.appendchild(handle); }; /*========== make an element draggable relative to it's parent ==========*/ var makedraggable = function makedraggable(elem, endfunction) { var offsettop; var offsetleft; elem.setattribute('data-draggable', 'true'); var dragstart = function dragstart(e) { e.preventdefault(); e.stoppropagation(); if (e.target.getattribute('data-draggable') !== 'true' || e.target !== elem || e.button !== 0) return; offsetleft = e.clientx - elem.offsetleft; offsettop = e.clienty - elem.offsettop; document.addeventlisten...
...ve', mousedrag); document.addeventlistener('mouseup', dragend); }; var dragend = function dragend(e) { if (e.button !== 0) return; document.removeeventlistener('mousemove', mousedrag); document.removeeventlistener('mouseup', dragend); }; var mousedrag = function mousedrag(e) { elem.style.left = e.clientx - offsetleft + 'px'; elem.style.top = e.clienty - offsettop + 'px'; }; elem.addeventlistener('mousedown', dragstart, false); }; return { makeresizable : makeresizable, makedraggable : makedraggable }; })(); /*========== color class ==========*/ var color = uicolorpicker.color; var hslcolor = uicolorpicker.hslcolor; /** * colorpalette */ var colorpalette = (function colorpalette() { var samples = []; var color_palette...
... null; }; canvassample.prototype.updateposition = function updateposition(posx, posy) { this.node.style.top = posy - this.starty + 'px'; this.node.style.left = posx - this.startx + 'px'; }; var canvasdropevent = function canvasdropevent(e) { var color = tool.getsamplecolorfrom(e); if (color) { var offsetx = e.pagex - canvas.offsetleft; var offsety = e.pagey - canvas.offsettop; var sample = new canvassample(color, offsetx, offsety); if (tutorial) { tutorial = false; canvas.removeattribute('data-tutorial'); var info = new canvassample(new color(), 100, 100); info.node.setattribute('data-tutorial', 'dblclick'); } } }; var setactivesample = function setactivesample(sample) { colorpickersamples.unsetactivesample(); tool.unsetv...

Build the brick field - Game development
var brickrowcount = 3; var brickcolumncount = 5; var brickwidth = 75; var brickheight = 20; var brickpadding = 10; var brickoffsettop = 30; var brickoffsetleft = 30; here we've defined the number of rows and columns of bricks , their width and height, the padding between the bricks so they won't touch each other and a top and left offset so they won't start being drawn right from the edge of the canvas.
...what we need to do is include some calculations that will work out the x and y position of each brick for each loop iteration: var brickx = (c*(brickwidth+brickpadding))+brickoffsetleft; var bricky = (r*(brickheight+brickpadding))+brickoffsettop; each brickx position is worked out as brickwidth + brickpadding, multiplied by the column number, c, plus the brickoffsetleft; the logic for the bricky is identical except that it uses the values for row number, r, brickheight, and brickoffsettop.
...brickx and bricky values as the coordinates instead of (0,0) each time, will look like this — add this into your code below the drawpaddle() function: function drawbricks() { for(var c=0; c<brickcolumncount; c++) { for(var r=0; r<brickrowcount; r++) { var brickx = (c*(brickwidth+brickpadding))+brickoffsetleft; var bricky = (r*(brickheight+brickpadding))+brickoffsettop; bricks[c][r].x = brickx; bricks[c][r].y = bricky; ctx.beginpath(); ctx.rect(brickx, bricky, brickwidth, brickheight); ctx.fillstyle = "#0095dd"; ctx.fill(); ctx.closepath(); } } } actually drawing the bricks the last thing to do in this lesson is to add a call to drawbricks() somewhere in the draw()...

VisualViewport - Web APIs
visualviewport.offsettop read only returns the offset of the top edge of the visual viewport from the top edge of the layout viewport in css pixels.
... var offsetleft = viewport.offsetleft; var offsettop = viewport.height - layoutviewport.getboundingclientrect().height + viewport.offsettop; // you could also do this by setting style.left and style.top if you // use width: 100% instead.
... bottombar.style.transform = 'translate(' + offsetleft + 'px,' + offsettop + 'px) ' + 'scale(' + 1/viewport.scale + ')' } window.visualviewport.addeventlistener('scroll', viewporthandler); window.visualviewport.addeventlistener('resize', viewporthandler); note: this technique should be used with care; emulating position: device-fixed in this way can result in the fixed element flickering during scrolling.

Border-image generator - CSS: Cascading Style Sheets
bscribe : subscribe, unsubscribe : unsubscribe }; })(); window.addeventlistener("load", function() { borderimage.init(); }); var borderimage = (function borderimage() { var getelembyid = document.getelementbyid.bind(document); var subject; var preview; var guidelines = []; var positions = ['top', 'right', 'bottom', 'left']; var makedraggable = function makedraggable(elem) { var offsettop; var offsetleft; elem.setattribute('data-draggable', 'true'); var dragstart = function dragstart(e) { if (e.target.getattribute('data-draggable') !== 'true' || e.target !== elem || e.button !== 0) return; offsetleft = e.clientx - elem.offsetleft; offsettop = e.clienty - elem.offsettop; document.addeventlistener('mousemove', mousedrag); document.addeventlistener('m...
...ouseup', dragend); }; var dragend = function dragend(e) { if (e.button !== 0) return; document.removeeventlistener('mousemove', mousedrag); document.removeeventlistener('mouseup', dragend); }; var mousedrag = function mousedrag(e) { elem.style.left = e.clientx - offsetleft + 'px'; elem.style.top = e.clienty - offsettop + 'px'; }; elem.addeventlistener('mousedown', dragstart, false); }; var previewcontrol = function previewcontrol() { var dragging = false; var valuex = null; var valuey = null; var dragstart = function dragstart(e) { if (e.button !== 0) return; valuex = e.clientx - preview.clientwidth; valuey = e.clienty - preview.clientheight; dragging = true; document.addeventlistener('mousemove', mousedrag); }; var dragend ...
... if (unit_topic) inputslidermanager.setstep(unit_topic, value); }; var show = function show(e) { var topic = e.target.getattribute('data-topic'); var precision = inputslidermanager.getprecision(topic); var step = inputslidermanager.getstep(topic); unit_topic = topic; title.textcontent = topic; panel.setattribute('data-active', 'true'); panel.style.top = e.target.offsettop - 40 + 'px'; panel.style.left = e.target.offsetleft + 30 + 'px'; inputslidermanager.setvalue('unit-precision', precision); inputslidermanager.setvalue('unit-step', step); }; var init = function init() { panel = document.createelement('div'); title = document.createelement('div'); var close = document.createelement('div'); step = inputslidermanager.createslider('unit-st...

Element.clientTop - Web APIs
as it happens, all that lies between the two locations (offsettop and client area top) is the element's border.
... this is because the offsettop indicates the location of the top of the border (not the margin) while the client area starts immediately below the border, (client area includes padding.) therefore, the clienttop value will always equal the integer portion of the .getcomputedstyle() value for "border-top-width".

HTMLElement - Web APIs
htmlelement.offsettop read only returns a double, the distance from this element's top border to its offsetparent's top border.
... working draft added the following properties: offsetparent, offsettop, offsetleft, offsetwidth, and offsetheight.

Index - Web APIs
1630 htmlelement.offsettop api, cssom view, needsmarkupwork, property, read-only, reference the htmlelement.offsettop read-only property returns the distance of the current element relative to the top of the offsetparent node.
... 4544 visualviewport.offsettop api, property, reference, visual viewport api, visualviewport, offsettop, viewport the offsettop read-only property of the visualviewport interface returns the offset of the top edge of the visual viewport from the top edge of the layout viewport in css pixels.

Visual Viewport API - Web APIs
var viewport = event.target; var offsetleft = viewport.offsetleft; var offsettop = viewport.height - layoutviewport.getboundingclientrect().height + viewport.offsettop; // you could also do this by setting style.left and style.top if you // use width: 100% instead.
... bottombar.style.transform = 'translate(' + offsetleft + 'px,' + offsettop + 'px) ' + 'scale(' + 1/viewport.scale + ')' }) } window.visualviewport.addeventlistener('scroll', viewporthandler); window.visualviewport.addeventlistener('resize', viewporthandler); specifications specification status comment visual viewport apithe definition of 'visualviewport' in that specification.

window.location - Web APIs
example #6: using bookmarks without changing the hash property: <!doctype html> <html> <head> <meta charset="utf-8"/> <title>mdn example</title> <script> function shownode (onode) { document.documentelement.scrolltop = onode.offsettop; document.documentelement.scrollleft = onode.offsetleft; } function showbookmark (sbookmark, busehash) { if (arguments.length === 1 || busehash) { location.hash = sbookmark; return; } var obookmark = document.queryselector(sbookmark); if (obookmark) { shownode(obookmark); } } </script> <style> span.intlink { cursor: pointer; color: #0000ff; text-decoration: underline; } </sty...
...", _chkowner, false); } else if (window.attachevent) { window.attachevent("onscroll", _chkowner); } return function (sbookmark, busehash) { var onode = document.queryselector(sbookmark); _scrolly = document.documentelement.scrolltop; _scrollx = document.documentelement.scrollleft; _bookmark = sbookmark; _usehash = busehash === true; _nodex = onode.offsetleft; _nodey = onode.offsettop; _itframe = 1; if (_scrollid === -1) { _scrollid = setinterval(_next, math.round(nduration / nframes)); } }; })(); specifications specification status comment html living standardthe definition of 'window.location' in that specification.

Window.pageYOffset - Web APIs
<iframe id="frame"> </iframe> <div id="info"> </div> javascript var frame = document.getelementbyid("frame"); var framedoc = frame.contentdocument; var info = document.getelementbyid("info"); var target = framedoc.getelementbyid("overview"); framedoc.scrollingelement.scrolltop = target.offsettop; info.innertext = "y offset after scrolling: " + frame.contentwindow.pageyoffset + " pixels"; the javascript code begins by getting into frame and info the <iframe> element that contains our content as well as the <div> element into which we'll output the result of our scroll position check.
... with the target element in hand, we set the scrolltop of the frame's scrollingelement to the offsettop of the target element.

Cubic Bezier Generator - CSS: Cascading Style Sheets
(); ctx.stroke(); ctx.closepath(); } else { alert('you need safari or firefox 1.5+ to see this demo.'); } } function mousedown(e) { var canvas = document.getelementbyid('bezier'); var x1 = cx(document.getelementbyid('x1').value); var y1 = cy(document.getelementbyid('y1').value); var x = e.pagex - canvas.offsetleft; var y = e.pagey - canvas.offsettop; var output = document.getelementbyid('output'); output.value = "(" + x + "," + y + ") should be (" + x1 + "," + y1 + ")"; if ((x1 + radius >= x) && (x1 - radius <= x) && (y1 + radius >= y) && (y1 - radius <= y)) { var output = document.getelementbyid('output'); output.value = "p1!"; dragsm = 1; } var x2 = cx(document.getelementbyid('x2').value); ...
...gsm != 0) { canvas.onmousemove = mousemove; } } function mouseup(e) { var output = document.getelementbyid('output'); output.value = "mouse up!"; dragsm = 0; canvas.onmousemove = null; } function mousemove(e) { if (dragsm != 0) { var canvas = document.getelementbyid('bezier'); var x = e.pagex - canvas.offsetleft; var y = e.pagey - canvas.offsettop; var output = document.getelementbyid('output'); output.value = "drag!"; if (dragsm == 1) { var x1 = document.getelementbyid('x1'); var y1 = document.getelementbyid('y1'); x1.value = reversex(x); x1.value = math.round(x1.value * 10000) / 10000; y1.value = reversey(y); y1.value = math.round(y1.value *...

Forms related code snippets - Archive of obsolete content
pt); this.container.appendchild(othead); this.current.setdate(1); this.writedays(); otarget.onclick = function () { if (otable.parentnode) { otable.parentnode.removechild(otable); return; } otable.style.zindex = nzindex++; otable.style.position = "absolute"; otable.style.left = otarget.offsetleft + "px"; otable.style.top = (otarget.offsettop + otarget.offsetheight) + "px"; otarget.parentnode.insertbefore(otable, otarget); }; ainstances.push(this); } datepicker.prototype.writedays = function () { const nendblanks = (this.current.getday() + bzeroismonday * 6) % 7, nend = amonthlengths[this.current.getmonth()] + nendblanks, ntotal = nend + ((7 - nend % 7) % 7); var otd, otr; ...