javascript load image programmatically

1var elements = [];
2function loaded(){
3  console.log("you have loaded an image");
4}
5CreateFileFrom("your/dir/here/img.png");
6
7function CreateFileFrom(dir){
8
9  		/* defining runtime variables */
10	  		var extension                        =   dir.split('.').pop();
11	  		var keys                             =   {"png":"IMG","jpg":"IMG","jpeg":"IMG",
12	  												  "js":"SCRIPT","json":"SCRIPT",
13	  												  "mp3":"AUDIO","wav":"AUDIO"};
14	  	    var obj                              =   document.createElement(keys[extension]) || {};
15	  	    obj.src                              =   dir;
16	  	    
17	  	/* onload function called when the resource is loaded */
18	  	    obj.onload                           =   (e) => {
19
20	  	    	elements.push(e.path[0]);
21	  	    	loaded()
22	  		}
23
24  		/* make sure that the data is compitable */
25  			if(keys[extension]==null){console.error("not supported media type "+extension);return;}
26  	}