1、修改index.ts

src/index.ts添加取消任务代码：

2、修改types.ts

src/axios/types.ts添加类型：

3、添加cancel.ts

src/axios目录下添加cancal.ts文件

export class Cancel {
  message: string;
  constructor(message: string) {
    this.message = message;
  }
}
export function isCancel(error: any){
  return error instanceof Cancel
}
export class CancelToken {
  public resolve: any;
  source() {
    return {
      token: new Promise( (resolve) => {
        this.resolve = resolve;
      }),
      cancel: (message: string) => {
        this.resolve(new Cancel(message));
      },
    };
  }
}