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Summary
Returns a Selection
object representing the range of text selected by the user or the current position of the caret.
Syntax
selection = window.getSelection();
selection
is aSelection
object. When cast to string, either by appending an empty string (""
) or usingString.toString()
, this object returns the text selected.
Example
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 aSelection
object.selectedText
is a string (Selected text).
Related objects
It's also useful to note that you can call Document.getSelection()
, which works identically.
HTML inputs provide simpler helper APIs for working with selection (see HTMLInputElement.setSelectionRange()
).
Notice the difference between selection and focus. Document.activeElement
returns the focused element.
Specifications
Specification | Status | Comment |
---|---|---|
HTML Editing APIs The definition of 'Window.getSelection()' in that specification. |
Editor's Draft | Initial definition |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | 9 | (Yes) | (Yes) |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | ? | ? | ? | ? | ? |