微信小程序,获取网络SVG图片宽高算法

该算法来源于小程序开发社区一位大佬帮我搞的.

/**
   * 获取网络SVG图片宽高
   * @param src SVG网络资源链接
   */
  public static GetSvgInfoFormUrl = (src: string): Promise<any> =>
    new Promise((resolve, reject) => {
      request({ url: src }).then((res: any) => {
        const { data } = res;
        // <svg height="" width=""
        const r1: RegExp = /(?:[Ss]+)?<svg(?=.*(height)="(d+)(?:[^"]+)?")(?=.*(width)="(d+)(?:[^"]+)?")(?:[Ss]+)?/;
        // <svg viewBox="0 0 1103 711"
        const r2: RegExp = /(?:[Ss]+)?viewBox="d+ d+ (d+) (d+)"(?:[Ss]+)?/;
        // <svg style="height:***px;***px"
        const r3: RegExp = /(?:[Ss]+)?(?:<svg[^>]+style="(?=.*(height):(d+)(?:[^>]+)?)(?=.*(width):(d+)(?:[^>]+)?))(?:[Ss]+)?/;
        let str: string = '{}';
        let info: {  number; height: number } = {  0, height: 0 };
        let isSuccess: boolean = false;
        try {
          str = data
            .replace(r1, '{"$1":$2,"$3":$4}')
            .replace(/$(2|4)/, '0')
            .replace(/$1/, 'height')
            .replace(/$3/, 'width');
          if (str.length > 45) isSuccess = false;
          else {
            isSuccess = true;
            info = JSON.parse(str);
          }
          if (!isSuccess) {
            str = data.replace(r2, '{"width":$1,"height":$2}').replace(/$(1|2)/, '0');
            if (str.length > 45) isSuccess = false;
            else {
              isSuccess = true;
              info = JSON.parse(str);
            }
            console.log('r2', info);
          }
          if (!isSuccess) {
            str = data
              .replace(r3, '{"$1":$2,"$3":$4}')
              .replace(/$(2|4)/, '0')
              .replace(/$1/, 'height')
              .replace(/$3/, 'width');
            if (str.length > 45) isSuccess = false;
            else {
              isSuccess = true;
              info = JSON.parse(str);
            }
            console.log('r3', info);
          }
        } catch (error) {
          console.log(error);
          reject(error);
        }
        if (isSuccess) resolve(info);
        else reject(new Error('无法正确解析SVG数据'));
      });
    });