KeyboardEvent keyIdentifier Property
Example
Get the identifier of the key that was pressed when a key event occured:
var x = event.keyIdentifier;
The result of x could be:
U+004B // U+004B is the letter "K" on the keyboard
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Definition and Usage
The keyIdentifier property returns the identifier of the key that was pressed when a key event occured.
Key identifiers are strings that identify keyboard buttons. The return value of this property can be a string of:
- A multicharacter (like "F1", "Enter", "HOME" or "CAPS LOCK")
- "U+" followed by a hexadecimal value (like "U+0041" for the A key, or "U+0035" for the 5 key)
The keyIdentifier property is only supported in Chrome, Safari and Opera 15 (and newer). However, there is a key property that is supported in Firefox and IE9 (and newer).
The key property also returns a string rather than a number. For function keys (multicharacter strings), it returns the same value as the keyIdentifier property; like "F1" and "Enter". However, for printable keys, it returns a single character string (like "a" or "F"), instead of the Unicode codepoint.
For a cross-browser solution, you could use both key and keyIdentifier in your code. However, because they both return different values, you cannot fully rely on the value being the kind that you want:
var x = event.key || event.keyIdentifier; // Use key or keyIdentifier, depending on browser support
Note: This property is read-only.
Tip: If you want to find out whether the "ALT", "CTRL", "META" or "SHIFT" key was pressed when a key event occured, use the altKey, ctrlKey, metaKey or shiftKey property.
Browser Support
The numbers in the table specify the first browser version that fully supports the property.
| Property | |||||
|---|---|---|---|---|---|
| keyIdentifier | Yes | Not supported | Not supported | Yes | 15.0 |
Syntax
event.keyIdentifier
Technical Details
| Return Value: |
A String, representing the identifier of the pressed keyboard button. Possible values:
|
|---|---|
| DOM Version: | DOM Level 3 Events |
More Examples
Example
A cross-browser solution to get the keyboard button that was pressed when a key event occured:
// Use key if the browser supports it, otherwise use keyIdentifier (for Chrome, Safari and Opera 15+)
var x = event.key || event.keyIdentifier;
The result of x could be:
F2
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Example
Alert some text if the user presses the "A" key:
var x = event.key || event.keyIdentifier;
/* If the pressed keyboard button is "a" or "A" (using caps lock or shift), alert some text.
The Unicode encoding of the character "a" (and "A") is "U+0041" (for keyIdentifier) */
if (x == "a" || x == "A" || x == "U+0041") {
alert ("You pressed the 'A' key!");
}
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Related Pages
HTML DOM reference: KeyboardEvent keyCode Property
HTML DOM reference: KeyboardEvent which Property
HTML DOM reference: KeyboardEvent charCode Property
❮ Event Object
