`New image()` and `document.createelement('img')` on canvas

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Receives an object containing image information as json and draws it on the canvas.
The following is the inside of the draw function.
In this case, which is better, createElement(img) or new Image()? and Why?

What I have tried:

JavaScript

canvas = document.getElementById('canvas'+id);
ctx = canvas.getContext('2d', {alpha:false});
ctx = fillStyle='#379fef';

/*object the contained img */

/** createElement **/
page.data.image = document.createElement('img');
page.data.image.src = page.data.src;

let img = page.data.image;
if(img.complete){
   ctx.drawImage(img,0,0);
}else{
   img.onload = function(){
       context.drawImage(img,0,0);
   }
}

/******** new image() *********/
let img = new Image();
img.src = page.data.src;
img.onload = function(){
    ctx.drawImage(img, 0, 0);
}

Posted 14-May-22 23:01pm

Chopin2001

Updated 15-May-22 22:33pm

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Richard Deeming · Accepted Answer · 2022-05-15T22:33:00

Image() - Web APIs | MDN[^]:
The Image() constructor creates a new HTMLImageElement instance. It is functionally equivalent to document.createElement('img').

The only difference between new Image() and document.createElement('img') is that one line is shorter than the other.

However, your two code blocks have other differences as well. Your first block stores the image in the page.data object, whereas the second block stores it in a local variable.

And neither block is entirely correct. You should assign the onload handler before assigning the src.