Base64 to Blob
This is based on someone else's code but I've lost the link. If you recognise your work leave a comment. It's here because I converted it to Typescript for convenient inclusion in Aurelia projects.
public base64ToBlob(b64Data: string, contentType: string = '', sliceSize = 512): Blob {
let byteCharacters = atob(b64Data);
let byteArrays = [];
for (let offset = 0; offset < byteCharacters.length; offset += sliceSize) {
let slice = byteCharacters.slice(offset, offset + sliceSize);
let byteNumbers = new Array(slice.length);
for (let i = 0; i < slice.length; i++) {
byteNumbers[i] = slice.charCodeAt(i);
}
let byteArray = new Uint8Array(byteNumbers);
byteArrays.push(byteArray);
}
return new Blob(byteArrays, { type: contentType });
}