Add downloadBlob

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@alttiri/util-js",
-  "version": "1.14.0-20240821",
+  "version": "1.14.1-20240908",
   "description": "Some util functions for personal use",
   "homepage": "https://github.com/AlttiRi/util-js",
   "keywords": [

src/util.ts

@@ -21,3 +21,28 @@ export function hashString(str: string): number {
     }
     return hash;
 }
+
+export type DownloadBlobOpt = {
+    /** The URL to be added as a hash in the downloaded blob URL. Useful to keep the original file URL. */
+    url?: string;
+    /** The delay before `revokeObjectURL`. 5000 by default. */
+    timeout?: number;
+}
+export function downloadBlob(blob: Blob, name: string, url?: string): void;
+export function downloadBlob(blob: Blob, name: string, opt: DownloadBlobOpt): void;
+export function downloadBlob(blob: Blob, name: string = "", urlOrOpts?: string | DownloadBlobOpt): void {
+    const anchor = document.createElement("a");
+    anchor.setAttribute("download", name || "");
+    const blobUrl = URL.createObjectURL(blob);
+    let url: string | undefined;
+    let timeout: number = 5000;
+    if (isString(urlOrOpts)) {
+        url = urlOrOpts;
+    } else {
+        url = urlOrOpts?.url;
+        timeout = urlOrOpts?.timeout || timeout;
+    }
+    anchor.href = blobUrl + (url ? ("#" + url) : "");
+    anchor.click();
+    setTimeout(() => URL.revokeObjectURL(blobUrl), timeout);
+}