515fceeb
 “wangming”
框架初始化
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/**
* @description: base64 to blob
*/
export function dataURLtoBlob(base64Buf: string): Blob {
const arr = base64Buf.split(',');
const typeItem = arr[0];
// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
const mime = typeItem!.match(/:(.*?);/)![1];
// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
const bstr = window.atob(arr[1]!);
let n = bstr.length;
const u8arr = new Uint8Array(n);
while (n--) {
// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
u8arr[n] = bstr.codePointAt(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 HTMLCanvasElement | null;
// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
const ctx = canvas!.getContext('2d');
const img = new Image();
img.crossOrigin = '';
img.addEventListener('load', () => {
if (!canvas || !ctx) {
// eslint-disable-next-line prefer-promise-reject-errors
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;
});
}
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