✨ Implement unique function for all canvas data type

src/js/View.js

@@ -506,6 +506,35 @@ export let View = (function () {
         });
     }
 
+    /**
+     * Return Blob corresponding to the current view
+     */
+    View.prototype.getCanvasBlob = async function (imgType, width, height, withLogo=true) {
+        const c = await this.getCanvas(imgType, width, height, withLogo);
+        return new Promise((resolve, reject) => {
+            c.toBlob(blob => {
+                if (blob) {
+                    resolve(blob);
+                } else {
+                    reject(new Error('Canvas toBlob failed'));
+                }
+            });
+        });
+    }
+
+    View.prototype.getViewData = async function (dataType, imgType, width, height, withLogo=true){
+        switch (dataType) {
+            case "url":
+                return await this.getCanvasDataURL(imgType, width, height, withLogo);
+            case "arraybuffer":
+                return await this.getCanvasArrayBuffer(imgType, width, height, withLogo);
+            case "blob":
+                return await this.getCanvasBlob(imgType, width, height, withLogo);
+            default:
+                throw new Error("Unknown data type: " + dataType);
+        }
+    }
+
     View.prototype.selectLayer = function (layer) {
         if (!this.imageLayers.has(layer)) {
             console.warn(layer + ' does not exists. So cannot be selected');