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The Window.getSelection() method returns a Selection object representing the range of text selected by the user or the current position of the caret.

Syntax

selection = window.getSelection();

Return value

A Selection object.

When cast to string, either by appending an empty string ("") or using Selection.toString(), this object returns the text selected.

When called on an <iframe> that is not displayed (eg. where display: none is set) Firefox will return null, whereas other browsers will return a Selection object with Selection.type set to None.

Examples

function foo() {
    var selObj = window.getSelection(); 
    alert(selObj);
    var selRange = selObj.getRangeAt(0);
    // do stuff with the range
}

Notes

String representation of the Selection object

In JavaScript, when an object is passed to a function expecting a string (like window.alert() or document.write()), the object's toString() method is called and the returned value is passed to the function. This can make the object appear to be a string when used with other functions when it is really an object with properties and methods.

In the above example, selObj.toString() is automatically called when it is passed to window.alert(). However, attempting to use a JavaScript String property or method such as length or substr directly on a Selection object will result in an error if it does not have that property or method and may return unexpected results if it does. To use a Selection object as a string, call its toString() method directly:

var selectedText = selObj.toString();
  • selObj is a Selection object.
  • selectedText is a string (Selected text).

You can call Document.getSelection(), which works identically to Window.getSelection().

It is worth noting that currently getSelection() doesn't work on the content of <input> elements in Firefox. HTMLInputElement.setSelectionRange()) could be used to work around this.

Notice also the difference between selection and focus. Document.activeElement returns the focused element.

Specifications

Specification Status Comment
Selection API
The definition of 'Window.getSelection()' in that specification.
Working Draft New spec.
HTML Editing APIs
The definition of 'Window.getSelection()' in that specification.
Editor's Draft Initial definition

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
getSelectionChrome Full support YesEdge Full support 12Firefox Full support YesIE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 55
Notes
Full support 55
Notes
Notes No support for selection events.
Opera Android Full support 37Safari iOS Full support 5.1
Notes
Full support 5.1
Notes
Notes No support for selection start.
Samsung Internet Android Full support Yes

Legend

Full support  
Full support
See implementation notes.
See implementation notes.

See also