HTMLElement: mscandidatewindowshow event

Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The mscandidatewindowshow event is thrown immediately after the Input Method Editor (IME) candidate window is set to appear, but before it renders.

This proprietary method is specific to Internet Explorer.

This event fires after the positioning information of the IME candidate window has been determined. You can obtain the positioning information using the getCandidateWindowClientRect method, and adjust your layout as needed to avoid any occlusions with the IME candidate window.

Web applications need only register for this event once per element (the handler will remain valid for the lifetime of the element).


Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("mscandidatewindowshow", (event) => {});

onmscandidatewindowshow = (event) => {};

Event type

A generic Event with no added properties.


in IE11, developers can detect the opening of the IME candidate window by listening to MSCandidateWindowShow event, then call getCandidateWindowClientRect() function to find out where the candidate window is and position the suggestion UI away from it:

const context = document.getElementById("mySearchBox").msGetInputContext();
context.addEventListener("MSCandidateWindowShow", candidateWindowShowHandler);

function candidateWindowShowHandler(e) {
  const imeRect = context.getCandidateWindowClientRect();
  const suggestionRect = document
  // Check if the two rects intersect, and position them away from each other.

When the IME candidate window changes position or closes, it fires mscandidatewindowupdate or mscandidatewindowhide events. Developers could listen to them and shift the suggestion UI accordingly.

See also