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JavaScript

Posted by moath alqutoob
moath alqutoob
2,450 Points

this code make me crazy

plz help me to understand this code

$(document).ready(function() {
    $(document).keydown(function(key) {
        switch(parseInt(key.which,10)) {
            // Left arrow key pressed
            case 37:
                $('img').animate({left: "-=10px"}, 'fast');
                break;
            // Up Arrow Pressed
            case 38:
                // Put our code here
                break;
            // Right Arrow Pressed
            case 39:
                // Put our code here
                break;
            // Down Arrow Pressed
            case 40:
                // Put our code here
                break;
        }
    });
});

1-keydown(function(key) why he put key in function what this key do

switch(parseInt(key.which,10))

10? key.which parseInt and the code

Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,696 Points
Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,696 Points

Formatted your code. From the Markdown Cheatsheet:

Wrap your code with 3 backticks (```) on the line before and after. If you specify the language after the first set of backticks, that'll help us with syntax highlighting.

        ```html
        <p>This is code!</p>
        ```

1 Answer

diego sepulveda
diego sepulveda
3,502 Points
diego sepulveda
diego sepulveda
3,502 Points

1-. He put key as parameter in that function because is a callback function, google that, so when the document is ready this means that page has load completely excute this function, saying $(document).keydown(function(key){}) this means listen to any key and excute this function and passing the parameter key you can use it to see what key was pressed