屏蔽F12审查元素，禁止修改页面代码

一、屏蔽F12 审查元素

document.onkeydown = function(){

    if(window.event && window.event.keyCode == 123) {
        alert("F12被禁用");
        event.keyCode=0;
        event.returnValue=false;
    }
    if(window.event && window.event.keyCode == 13) {
        window.event.keyCode = 505;
    }
    if(window.event && window.event.keyCode == 8) {
        alert(str+"\n请使用Del键进行字符的删除操作！");
        window.event.returnValue=false;
    }

}

如果想要禁用右键  不提示可以使用下面的代码

document.onkeydown = function(){

    if(window.event && window.event.keyCode == 123) {
       
        event.keyCode=0;
        event.returnValue=false;
    }
    if(window.event && window.event.keyCode == 13) {
        window.event.keyCode = 505;
    }
    if(window.event && window.event.keyCode == 8) {
        alert(str+"\n请使用Del键进行字符的删除操作！");
        window.event.returnValue=false;
    }

}

二、屏蔽右键菜单

document.oncontextmenu = function (event){
if(window.event){
event = window.event;
}try{
var the = event.srcElement;
if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")){
return false;
}
return true;
}catch (e){
return false;
}
}

三、屏蔽粘贴

document.onpaste = function (event){
if(window.event){
event = window.event;
}try{
var the = event.srcElement;
if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")){
return false;
}
return true;
}catch (e){
return false;
}
}

四、屏蔽复制

document.oncopy = function (event){
if(window.event){
event = window.event;
}try{
var the = event.srcElement;
if(!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")){
return false;
}
return true;
}catch (e){
return false;
}
}

五、屏蔽剪切

document.oncut = function (event){
if(window.event){
event = window.event;
}try{
var the = event.srcElement;
if(!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")){
return false;
}
return true;
}catch (e){
return false;
}
}

六、屏蔽选中

document.onselectstart = function (event){
    if(window.event){
        event = window.event;
    }try{
    var the = event.srcElement;
    if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName =="TEXTAREA")){
        return false;
    }
    return true;
    } catch (e) {
        return false;
    }
}