catalog-ui/src/app/ng2/services/file-utils.service.ts

   1 import { Injectable } from "@angular/core";
   2 import { WindowRef } from "./window.service";
   3
   4 @Injectable()
   5 export class FileUtilsService {
   6     constructor(private windowRef: WindowRef){}
   7
   8         public byteCharactersToBlob = (byteCharacters, contentType):any => {
   9             contentType = contentType || '';
  10             let sliceSize = 1024;
  11             let bytesLength = byteCharacters.length;
  12             let slicesCount = Math.ceil(bytesLength / sliceSize);
  13             let byteArrays = new Array(slicesCount);
  14
  15             for (let sliceIndex = 0; sliceIndex < slicesCount; ++sliceIndex) {
  16                 let begin = sliceIndex * sliceSize;
  17                 let end = Math.min(begin + sliceSize, bytesLength);
  18
  19                 let bytes = new Array(end - begin);
  20                 for (let offset = begin, i = 0; offset < end; ++i, ++offset) {
  21                     bytes[i] = byteCharacters[offset].charCodeAt(0);
  22                 }
  23                 byteArrays[sliceIndex] = new Uint8Array(bytes);
  24             }
  25             return new Blob(byteArrays, {type: contentType});
  26         };
  27
  28         public base64toBlob = (base64Data, contentType):any => {
  29             let byteCharacters = atob(base64Data);
  30             return this.byteCharactersToBlob(byteCharacters, contentType);
  31         };
  32
  33         public downloadFile = (blob, fileName):void=> {
  34             let url = this.windowRef.nativeWindow.URL.createObjectURL(blob);
  35             let downloadLink = document.createElement("a");
  36
  37             downloadLink.setAttribute('href', url);
  38             downloadLink.setAttribute('download', fileName);
  39             document.body.appendChild(downloadLink);
  40
  41             var clickEvent = new MouseEvent("click", {
  42                 "view": window,
  43                 "bubbles": true,
  44                 "cancelable": true
  45             });
  46             downloadLink.dispatchEvent(clickEvent);
  47         }
  48 }