浏览器FileReader读取图片尺寸

[981377660LMT]

export async function getImageSize (file: File): Promise<[width: number, height: number]> {
  return new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onload = (event) => {
      const img = new Image();
      img.onload = () => {
        resolve([img.width, img.height]);
      };
      img.onerror = (error) => {
        reject(error);
      };
      img.src = event.target?.result as string;
    };
    reader.onerror = (error) => {
      reject(error);
    };
    reader.readAsDataURL(file);
  });
}