l兩種獲取本地圖片轉BASE64 的方式

canvas.toDataURL() 轉換base64  

ToBase64(imgUrl) {
function getBase64Image(img) {
var canvas = document.createElement(“canvas”);
canvas.width = 200;
canvas.height = 200;
var ctx = canvas.getContext(“2d”);
ctx.drawImage(img, 0, 0, img.width, img.height);
var ext = img.src.substring(img.src.lastIndexOf(".")+1).toLowerCase();
var dataURL = canvas.toDataURL(“image/”+ext);
return dataURL;
}
var img = imgUrl;
var image = new Image();
image.src = img;
image.onload = function(){
this.base64Img = getBase64Image(image);
console.log(this.base64Img);
}

 

XMLHttpRequest  配合 readAsDataURl 獲取本地資源轉base64

getBase64(imgUrl){

    window.URL = window.URL || Window.weblitURL;

    const xhr =new XMLHttpRequest()

    xhr.open('get',imgUrl,true)

    xhr.responseType = 'blob';

    xhr.οnlοad=()=>{

        if(xhr.status ==200){

            const blob =xhr.response;

            const oFileReader =new FileReader();

            oFileReader.readAsDataURL(blob);

            oFileReader.onload = e=>{

                const  base64 = e.target.result;

            }

        }

    }

}