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JavaScript function name alt ()

If the function name is "alt", I get the error: "alt is not a function". All other names work. Here is the code:

<!DOCTYPE HTML>
<html>
    <head>
    </head>
    <body>
        <input type="button" value="click me" onclick="alt('dato',28);"/>
        <script type="text/javascript">
            window.onload = function(){
                alt = function(name,age){
                    alert(name + "  " + age);
                }
            }
        </script>
    </body>
</html>

Please change the name of the function from "alt" to whatever is allowed to see that it works.

Can anyone explain what is happening?

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3 answers

, , , onclick this . alt - , , alt HTML ( alt input, ).

, alt window.alt, script, element alt, .

, onclick="alt('dato',28);", : onclick="this.alt('dato',28);".

alt, , alt, HTML, , :

onclick="window.alt('dato',28);"
+5

, , , window.alt HTMLInputElement.prototype.alt

10 :

  • H , Scope NewObjectEnvironment (, ).

    H Window object : - .

  • null, Scope NewObjectEnvironment ( , ).

  • NULL, Scope NewObjectEnvironment (element, Scope).

: NewObjectEnvironment() ECMAScript 5 10.2.2.3 NewObjectEnvironment (O, E)

, .

  • function alt__(name,age){
  alert(name + "  " + age);
}
    <input type="button" value="click me" onclick="alt__('dato',28)" />
    Hide result

  • window.alt (, Window ):

    <input type="button" value="click me" onclick="window.alt('dato',28)" />


    function alt(name,age){
  alert(name + "  " + age);
}
    <input type="button" value="click me" onclick="window.alt('dato',28)" />
    Hide result

  • IDL content 1:

    theInput.onclick = function(){ alt('dato',28); });


    function alt(name,age){
  alert(name + "  " + age);
}
document.querySelector('input').onclick = function(){
  alt('dato',28);
};
    <input type="button" value="click me" />
    Hide result

  • :

    theInput.addEventListener('click', function(){ alt('dato',28); });


    function alt(name,age){
  alert(name + "  " + age);
}
document.querySelector('input')


----------

.addEventListener('click', function(){
  alt('dato',28);
});
    <input type="button" value="click me" />
    Hide result
+3

You cannot use html attribute names as functions in attribute values ​​because it refers to the attribute value.

eg

<input type="button" value="click me" onclick="console.log(value)" />

there will be a console magazine "click me"

http://jsfiddle.net/z45dbxL4/

Implied this. Same as

<input type="button" value="click me" onclick="console.log(this.value)" />
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Source: https://habr.com/ru/post/1610123/

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