Selection.rangeCount - Web APIs 编辑

Experimental

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The Selection.rangeCount read-only property returns the number of ranges in the selection.

Before the user has clicked a freshly loaded page, the rangeCount is 0. After the user clicks on the page, rangeCount is 1, even if no selection is visible.

A user can normally only select one range at a time, so the rangeCount will usually be 1. Scripting can be used to make the selection contain more than one range.

Gecko browsers allow multiple selections across table cells. Firefox allows to select multiple ranges in the document by using Ctrl+click (unless the click occurs within an element that has the display: table-cell CSS property assigned).

Syntax

value = sel.rangeCount

Example

The following example will show the rangeCount every second. Select text in the browser to see it change.

HTML

<table>
  <tr><td>a.1<td>a.2
  <tr><td>b.1<td>b.2
  <tr><td>c.1<td>c.2

JavaScript

window.setInterval(function () {
  console.log(window.getSelection().rangeCount);
}, 1000);

Result

Open your console to see how many ranges are in the selection. In Gecko browsers, you can select multiple ranges across table cells by holding down Ctrl while dragging with the mouse.

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• Selection, the interface it belongs to.