There is a difference between onkeypress and onkeydown. The following will explain the difference between onkeypress and onkeydown events.
The onkeypress event occurs when the user presses and releases any alphanumeric keys. However, the system buttons (for example: arrow keys, function keys) cannot be recognized.
The onkeydown event occurs when the user presses any keyboard keys (including system buttons).
Specific differences：
1. One is let go and the other is not let go, onkeydown occurs before onkeypress.
System button cannot be used.
The captured keyCode does not distinguish between letter sizes, while onkeypress distinguishes.
onkeypress occurs when the user presses and releases any alphanumeric keys. System buttons (for example, arrow keys and function keys) are not recognized.
onkeyup occurs when the user releases any previously pressed keyboard keys.
onkeydown occurs when the user presses any keyboard keys (including system buttons, such as arrow keys and function keys).
onkeypress
As of Microsoft® Internet Explorer 4.0, the onkeypress event fires and can be canceled for the following keys:
Letters: A - Z (uppercase and lowercase)
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: ESC, SPACEBAR, ENTER
onkeydown
As of Microsoft® Internet Explorer 4.0, the onkeydown event fires for the following keys:
Editing: DELETE, INSERT
Function: F1 - F12
Letters: A - Z (uppercase and lowercase)
Navigation: HOME, END, LEFT ARROW, RIGHT ARROW, UP ARROW, DOWN ARROW
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: ESC, SPACEBAR, SHIFT, TAB
As of Internet Explorer 5, the event also fires for the following keys:
Editing: BACKSPACE
Navigation: PAGE UP, PAGE DOWN
System: SHIFT+TAB
As of Internet Explorer 5, this event can be canceled for the following keys and key combinations by specifying =false:
Editing: BACKSPACE, DELETE
Letters: A - Z (uppercase and lowercase)
Navigation: PAGE UP, PAGE DOWN, END, HOME, LEFT ARROW, RIGHT ARROW, UP ARROW, DOWN ARROW
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: SPACEBAR, ESC, TAB, SHIFT+TAB
You can cancel all keys that fire the onkeydown event in HTML Applications, including most accelerator keys, such as ALT+F4.
In Internet Explorer 4.0, you cannot cancel the onkeydown event, but you can use the onkeypress event to cancel keyboard events.
Press the two together, like this:
The onkeypress event occurs when the user presses and releases any alphanumeric keys. However, the system buttons (for example: arrow keys, function keys) cannot be recognized.
The onkeydown event occurs when the user presses any keyboard keys (including system buttons).
Specific differences：
1. One is let go and the other is not let go, onkeydown occurs before onkeypress.
System button cannot be used.
The captured keyCode does not distinguish between letter sizes, while onkeypress distinguishes.
onkeypress occurs when the user presses and releases any alphanumeric keys. System buttons (for example, arrow keys and function keys) are not recognized.
onkeyup occurs when the user releases any previously pressed keyboard keys.
onkeydown occurs when the user presses any keyboard keys (including system buttons, such as arrow keys and function keys).
onkeypress
As of Microsoft® Internet Explorer 4.0, the onkeypress event fires and can be canceled for the following keys:
Letters: A - Z (uppercase and lowercase)
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: ESC, SPACEBAR, ENTER
onkeydown
As of Microsoft® Internet Explorer 4.0, the onkeydown event fires for the following keys:
Editing: DELETE, INSERT
Function: F1 - F12
Letters: A - Z (uppercase and lowercase)
Navigation: HOME, END, LEFT ARROW, RIGHT ARROW, UP ARROW, DOWN ARROW
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: ESC, SPACEBAR, SHIFT, TAB
As of Internet Explorer 5, the event also fires for the following keys:
Editing: BACKSPACE
Navigation: PAGE UP, PAGE DOWN
System: SHIFT+TAB
As of Internet Explorer 5, this event can be canceled for the following keys and key combinations by specifying =false:
Editing: BACKSPACE, DELETE
Letters: A - Z (uppercase and lowercase)
Navigation: PAGE UP, PAGE DOWN, END, HOME, LEFT ARROW, RIGHT ARROW, UP ARROW, DOWN ARROW
Numerals: 0 - 9
Symbols: ! @ # $ % ^ & * ( ) _ - + = < [ ] { } , . / ? \ | ' ` " ~
System: SPACEBAR, ESC, TAB, SHIFT+TAB
You can cancel all keys that fire the onkeydown event in HTML Applications, including most accelerator keys, such as ALT+F4.
In Internet Explorer 4.0, you cannot cancel the onkeydown event, but you can use the onkeypress event to cancel keyboard events.
Press the two together, like this: