feat: the cache can be configured to be encrypted

src/utils/file/base64Conver.ts

@@ -0,0 +1,41 @@
+/**
+ * @description: base64 to blob
+ */
+export function dataURLtoBlob(base64Buf: string): Blob {
+  const arr = base64Buf.split(',');
+  const typeItem = arr[0];
+  const mime = typeItem.match(/:(.*?);/)![1];
+  const bstr = atob(arr[1]);
+  let n = bstr.length;
+  const u8arr = new Uint8Array(n);
+  while (n--) {
+    u8arr[n] = bstr.charCodeAt(n);
+  }
+  return new Blob([u8arr], { type: mime });
+}
+
+/**
+ * img url to base64
+ * @param url
+ */
+export function urlToBase64(url: string, mineType?: string): Promise<string> {
+  return new Promise((resolve, reject) => {
+    let canvas = document.createElement('CANVAS') as Nullable<HTMLCanvasElement>;
+    const ctx = canvas!.getContext('2d');
+
+    const img = new Image();
+    img.crossOrigin = '';
+    img.onload = function () {
+      if (!canvas || !ctx) {
+        return reject();
+      }
+      canvas.height = img.height;
+      canvas.width = img.width;
+      ctx.drawImage(img, 0, 0);
+      const dataURL = canvas.toDataURL(mineType || 'image/png');
+      canvas = null;
+      resolve(dataURL);
+    };
+    img.src = url;
+  });
+}