使用 JavaScript 獲取圖片 base64 編碼格式的文本

function getBase64Image(img) {     // Create an empty canvas element     var canvas = document.createElement("canvas");     canvas.width = img.width;     canvas.height = img.height;     // Copy the image contents to the canvas     var ctx = canvas.getContext("2d");     ctx.drawImage(img, 0, 0);     // Get the data-URL formatted image     // Firefox supports PNG and JPEG. You could check img.src to     // guess the original format, but be aware the using "image/jpg"     // will re-encode the image.     var dataURL = canvas.toDataURL("image/png");     return dataURL.replace(/^data:image\/(png|jpg);base64,/, ""); }