React Native 提供了和 web 标准一致的Fetch API、内置了XMLHttpRequest API和WebSocket，用于满足开发者访问网络的需求。

一、JSON请求

fetch('https://mywebsite.com/mydata.json');

二、POST请求

1、application/json

fetch('https://mywebsite.com/endpoint/', {
  method: 'POST',
  headers: {
    Accept: 'application/json',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    firstParam: 'yourValue',
    secondParam: 'yourOtherValue'
  })
});

2、application/x-www-form-urlencoded

fetch('https://mywebsite.com/endpoint/', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/x-www-form-urlencoded'
  },
  body: 'key1=value1&key2=value2'
});

三、数据响应

fetch('https://facebook.github.io/react-native/movies.json')
    .then((response) => response.json())
    .then((responseJson) => {
      return responseJson.movies;
    })
    .catch((error) => {
      console.error(error);
    });

四、async await异步等待

async function getMoviesFromApi() {
  try {
    let response = await fetch('https://facebook.github.io/react-native/movies.json');
    let responseJson = await response.json();
    return responseJson.movies;
  } catch (error) {
    console.error(error);
  }
}

五、XMLHttpRequest

const request = new XMLHttpRequest();
request.onreadystatechange = (e) => {
  if (request.readyState !== 4) {
    return;
  }

  if (request.status === 200) {
    console.log('success', request.responseText);
  } else {
    console.warn('error');
  }
};

request.open('GET', 'https://mywebsite.com/endpoint/');
request.send();

六、WebSocket

const ws = new WebSocket('ws://host.com/path');

ws.onopen = () => {
  // connection opened
  ws.send('something'); // send a message
};

ws.onmessage = (e) => {
  // a message was received
  console.log(e.data);
};

ws.onerror = (e) => {
  // an error occurred
  console.log(e.message);
};

ws.onclose = (e) => {
  // connection closed
  console.log(e.code, e.reason);
};

参考链接：

• https://reactnative.cn/docs/network