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存在诸如Overloadsfor 之类的东西class？我创建了与 createRequest.ts 相关的先前问题，该函数应该没有错误。我想为函数中的class Data类似泛型定义相同的泛型createRequest。

错误

错误：(31, 52) TS2345：“RequestParameters”类型的参数不可分配给“RequestParameters & { as?: "json" | 类型的参数 不明确的; }'。类型 'RequestParameters' 不能分配给类型 '{ as?: "json" | 不明确的; }'。'as' 的属性类型是不兼容的。输入'"json" | “文本” | undefined' 不能分配给类型 '"json" | 不明确的'。类型 '"text"' 不能分配给类型 '"json" | 不明确的'。

数据.tsx

import * as React from 'react';

import createRequest, { RequestParameters, } from '../../createRequest';

interface P<R> {
  children: (children: { createRequest: Data<R>['createRequest'] } & S<R>) => React.ReactNode;
  parameters: RequestParameters;
  url: Parameters<typeof createRequest>[0];
}

interface S<R> {
  error: Error | null;
  response: R | null;
}

class Data<R> extends React.Component<P<R>, S<R>> {
  async componentDidMount () {
    await this.createRequest();
  }

  state = { error: null, response: null, };

  createRequest = async (): Promise<void> => {
    this.setState(() => ({ error: null, response: null, }));

    try {
      const { parameters, url, } = this.props;

      const response = await createRequest<R>(url, parameters); // <-- Error

      this.onResponse(response);
    } catch (error) {
      this.onError(error);
    }
  };

  onError (error: Error): void {
    this.setState(() => ({ error, }));

    throw error;
  }

  onResponse (response: R): void {
    this.setState(() => ({ response, }));
  }

  render () {
    const { children, } = this.props;

    return children({ createRequest: this.createRequest, ...this.state, });
  }
}

export default Data;

创建请求文件

import { isString, } from '@redred/helpers';

export interface RequestParameters {
  as?: 'json' | 'text';
  body?: FormData | URLSearchParams | null | string;
  headers?: Array<Array<string>> | Headers | { [name: string]: string };
  method?: string;
  queries?: { [name: string]: string };
}

async function createRequest (url: URL | string, parameters: RequestParameters & { as: 'text' }): Promise<string>;
async function createRequest<R> (url: URL | string, parameters: RequestParameters & { as?: 'json' }): Promise<R>;
async function createRequest<R> (url: URL | string, parameters: RequestParameters): Promise<R | string> {
  if (isString(url)) {
    url = new URL(url);
  }

  if (parameters.queries) {
    for (const name in parameters.queries) {
      url.searchParams.set(name, parameters.queries[name]);
    }
  }

  const response = await fetch(url.toString(), parameters);

  if (response.ok) {
    switch (parameters.as) {
      case 'json':
        return response.json();
      case 'text':
        return response.text();
      default:
        return response.json();
    }
  }

  throw new Error('!');
}

export default createRequest;