36 lines
1.3 KiB
TypeScript
36 lines
1.3 KiB
TypeScript
export function getBase64(img: Blob | File, callback: (base64: string) => void) {
|
|
const reader = new FileReader();
|
|
reader.addEventListener('load', () => callback(reader.result as string));
|
|
reader.readAsDataURL(img);
|
|
}
|
|
|
|
export function dataUrlToBlob(dataUrl: string) {
|
|
const base64ImageContent = dataUrl.replace(/^data:[a-z]+\/[a-z]+;base64,/, '');
|
|
const mimeSearch = dataUrl.match(/^data:([a-z]+\/[a-z]+)(;base64,)/);
|
|
if (!mimeSearch || mimeSearch.length !== 3) {
|
|
throw new Error(
|
|
'dataUrlToBlob could not find mime type, or base64 was missing: ' +
|
|
dataUrl.substring(0, 200),
|
|
);
|
|
} else {
|
|
return base64ToBlob(base64ImageContent, mimeSearch[1]);
|
|
}
|
|
}
|
|
|
|
export function base64ToBlob(base64: string, mime: string) {
|
|
mime = mime || '';
|
|
const sliceSize = 1024;
|
|
const byteChars = window.atob(base64);
|
|
const byteArrays = [];
|
|
for (let offset = 0, len = byteChars.length; offset < len; offset += sliceSize) {
|
|
const slice = byteChars.slice(offset, offset + sliceSize);
|
|
const byteNumbers = new Array(slice.length);
|
|
for (let i = 0; i < slice.length; i++) {
|
|
byteNumbers[i] = slice.charCodeAt(i);
|
|
}
|
|
const byteArray = new Uint8Array(byteNumbers);
|
|
byteArrays.push(byteArray);
|
|
}
|
|
return new Blob(byteArrays, { type: mime });
|
|
}
|