window.onmouseleave = window.onblur = window.onmouseout = document.onmouseleave = document.onblur = document.onmouseout = document.body.onmouseleave = document.body.onblur = document.body.onmouseout = onmouseleave = onblur = onmouseout = function(){
    //這里可以加入切屏警告代碼，一般為了防止學生誤操作，可以加入切屏第幾次的提示，剩余多少次(我們一般就用3次），3次之后就徹底關掉網頁，或者自動提交考試內容
};

防止考生復制考試題目或者答案內容

window.onselectstart = document.onselectstart = document.body.onselectstart = onselectstart = document.querySelector("html").onselectstart = function(){
    //這里用 return false 來防止選中復制內容，也可以寫復制其他禁止考試內容
};
 
防止考生用右鍵菜單復制內容

window.oncopy = window.onpaste = document.oncopy = document.onpaste = document.body.oncopy = document.body.onpaste = oncopy = onpaste = function(){
    //這里用 return false 來防止復制粘貼內容，也可以寫復制其他禁止考試內容
};

window.oncontextmenu = document.oncontextmenu = document.body.oncontextmenu = oncontextmenu = document.querySelector("html").oncontextmenu = function(){
    //return false 防止考生使用右鍵菜單
};

針對ctrl+shift+C以及F12做了屏蔽

 window.onkeyup = window.onkeydown = window.onKeyPress = document.onkeyup = document.onkeydown = document.onKeyPress = document.body.onkeyup = document.body.onkeydown = document.body.onKeyPress = onkeyup = onkeydown = onKeyPress = function(){
    //防止學生使用快捷鍵組合
};