react native 之異步請求

第一章 異步請求  fetch的運用

在react native  中異步請求一般用fetch這個方法, fetch的格式如下:

const params ={
    "charset":"utf-8","sessionToken":"dedbde5567e444a2b71b36ba7af9d7c5",
    "sessionRandom":"","requestNo":"99999991470815595421","channelCode":"001",
    "clientId":"9999999","transCode":"99002",
    "requestBodyJson":"{\"mobile\":\"13311223322\",\"password\":\"000000\",\"deviceNo\":\"1470815595420##\",\"requestType\":\"0\"}",
    "mobile":"13311223322","empNo":"","devicesn":"1470815595421","url":"/access/doSubmit.do"

}




function login(username, password, success, failure) {

    fetch('http://bxxsit.cpic.com.cn/sxtbweb/service/access/doSubmit.do',{
        method :'POST',
        headers:{
            'Accept': 'application/json',
            'Content-Type': 'application/json',
        },
        body:JSON.stringify(params)
    })
        .then((response) =>response.json())
        .then((responseJson) => {
          alert(JSON.stringify(responseJson))
          AsyncStorage.setItem('message',JSON.stringify(responseJson),()=>{
        // AsyncStorage.mergeItem('person',JSON.stringify(getState()),() =>{
        //});
           })
             })
      .catch((error) => {
            alert ("Failed")
      });


}

注意參數的寫法與回調函數的寫法.

 

第二章 異步請求的優化