encoding base64 and saving it to server javascript - javascript

I am trying to make it so that a user can upload an image and get the image encoded and saved into database and server. I do not have any experience with base64. I have the rest of my inputs saving, just cant figure out how to save image. my html code is
<input id="inputFileToLoad" type="file" onchange="encodeImageFileAsURL();"
accept="image/gif, image/jpeg, image/png" />
<div id="imgTest"></div>
my javascript is as follows and i ge an error thatt prompts encodeImageFileAsURL() is not defined.
function encodeImageFileAsURL() {
var filesSelected = document.getElementById("inputFileToLoad").files;
if (filesSelected.length > 0) {
var fileToLoad = filesSelected[0];
var fileReader = new FileReader();
fileReader.onload = function(fileLoadedEvent) {
var srcData = fileLoadedEvent.target.result; // <--- data: base64
var newImage = document.createElement('img');
newImage.src = srcData;
document.getElementById("imgTest").innerHTML = newImage.outerHTML;
alert("Converted Base64 version is " +
document.getElementById("imgTest").innerHTML);
console.log("Converted Base64 version is " +
document.getElementById("imgTest").innerHTML);
}
fileReader.readAsDataURL(fileToLoad);
}
}
all help is appreciated thank you.

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