Window. event object

1. event indicates the event status, such as the element that triggers the event object, the location and status of the mouse, and the key to be pressed. The event object is valid only when an event occurs. Some Properties of the event only make sense for specific events. For example, the fromelement and toelement attributes only make sense for onmouseover and onmouseout events.

2. attributes:

Altkey, button, Member, clientx, clienty, ctrlkey, fromelement, keycode, offsetx, offsety, propertyname, returnvalue, screenx, screeny, delimiter, srcelement, srcfilter, toelement, type, X, Y

3. Attribute details:

Attribute name	Description	Value	Description
Altkey	Check the status of the Alt key	When the Alt key is pressed, the value is true; otherwise, the value is false.	Read-Only
Shiftkey	Check the Shift key status	When the Shift key is pressed, the value is true; otherwise, the value is false.	Read-Only
Ctrlkey	Check the ctrl key status	When the ctrl key is pressed, the value is true; otherwise, the value is false.	Read-Only
Example: the status of the Special keys is displayed when you click the button) <Input type = "button" value = "click" onclick = "showstate ()"/> <SCRIPT> Function show (){ Alert ("altkey:" + window. event. altkey + "\ Nshiftkey:" + window. event. shiftkey + "\ Nctrlkey:" + window. event. ctrlkey ); } </SCRIPT>
Keycode	Detect the internal code corresponding to the keyboard event		It can be read and written, and can be any Unicode keyboard internal code. If no keyboard event is triggered, the value is 0.
Example: press the Enter key to make the next component focus. Press the tab key instead) <Input type = "text" onkeydown = "nextblur ()"/> <Input type = "text"/> <SCRIPT> Function nextblur (){ If (window. event. keycode = 13) // The Return key code Window. event. keycode = 9; // code of the tab key } </SCRIPT>
Srcelement	Returns the element of the trigger event.	Object	Read-Only
Example: (the name value of the button is displayed when you click the button) <Input type = "button" value = "" name = "Fujian" onclick = "show ()"/> <Input type = "button" value = "" name = "Jiangxi" onclick = "show ()"/> <SCRIPT> Function show (){ Alert (window. event. srcelement. Name ); } </SCRIPT>
X, Y	Position of the mouse relative to the current Browser	Px	Read-Only
Clientx, clienty	The current location of the mouse relative to the webpage	Px	Read-Only
Offsetx, offsety	The current location of the mouse relative to a certain area of the webpage	Px	Read-Only
Screenx, screeny	Position relative to User display	Px	Read-Only
Note: When you click a button (x, clientx, offsetx, screenx), you can easily understand offsetx. After you restore the IE window, you can obtain (x, clientx, screenx ), you will understand screenx. When you change the position of the DIV property between absolute and relative, you will understand the difference between x and clientx.
Returnvalue	Set or check the value returned from the event	The value in the true event is returned. False: the default operation of events on the source object is canceled.	Read/write
For example, right-click shielding, CTRL + N, Shift + F10, F5 refresh, and backspace Function keydown (){ // Shield right-click, CTRL + N, Shift + F10, F5 refresh, and backspace key If (window. event. altkey )&& (Window. event. keycode = 37) | // mask Alt + direction key seek (Window. event. keycode = 39) {// mask Alt + direction key → Event. returnvalue = false; // prevents the use of ALT + arrow keys to forward or backward webpages } If (event. keycode = 8) | // shield the unregeed deletion key (Event. keycode = 116) | // block the F5 refresh key (Event. keycode = 112) | // blocked F1 refresh key bitscn.com China Network Management Alliance (Event. ctrlkey & event. keycode = 82) {// Ctrl + R Event. keycode = 0; Event. returnvalue = false; } If (event. ctrlkey) & (event. keycode = 78) // block Ctrl + n Event. returnvalue = false; If (event. shiftkey) & (event. keycode = 121) // block SHIFT + F10 Event. returnvalue = false; If (window. event. srcelement. tagname = "A" & window. event. shiftkey) Window. event. returnvalue = false; // block shift with the left mouse button to open a new page If (window. event. altkey) & (window. event. keycode = 115) {// block Alt + F4 Window. showmodelessdialog ("about: blank", "", "dialogwidth: 1px; dialogheight: 1px "); Return false ;} }
Button	Check the pressed mouse key	0 without buttons 1 left click 2. Right-click 3. Press the Left or Right key. 4. Press the intermediate key 5. Press the left and intermediate keys. 6. Right-click and select intermediate key. 7. Press all keys	Only used for onmousedown, onmouseup, and onmousemove events. For other events, no matter the mouse status, 0 (such as onclick) is returned)
Srcelement	Detects the elements that the mouse leaves when the onmouseover and onmouseout events occur.	Object	Read-Only
Toelement	Detects the elements that the mouse enters when the onmouseover and onmouseout events occur.	Object	Read-Only
Type	Returned event name		The name of an event without a prefix of "on" is returned. For example, the Type returned by the onclick event is click.