Javascript code _ javascript tips for right-clicking, Ctrl + n, shift + F10, F5 refresh, and Backspace

Javascript code that shields the right-click, Ctrl + n, shift + F10, F5 refresh, and backspace keys
Function KeyDown (){
If (window. event. altKey )&&
(Window. event. keyCode = 37) | // mask Alt + direction key seek
(Window. event. keyCode = 39) {// mask Alt + direction key →
Alert ("you are not allowed to use ALT + arrow keys to move forward or backward the webpage! ");
Event. returnValue = false;
}

/* Note: this does not really block Alt + direction keys,
Because when the Alt + direction key pop-up warning box is displayed, press and hold the Alt key,
With the mouse clicked off the warning box, this blocking method will become invalid. If
Which of the following methods does the master really block the Alt key. */

If (event. keyCode = 8) | // shield the unregeed deletion key
(Event. keyCode = 116) | // block the F5 refresh key
(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 ;}
}



Function init ()
{
Try {announceDiv. innerText = announce;} catch (e ){}
}
Window. onload = init;