Question

doSetTimeout = (value, timer) => {
    setTimeout(() => {
      value
    }, timer);
  }

在此处致电doSetTimeout：

let Data = [
{"name":"John","age":"25"},
{"name":"Alex","age":"31"},
{"name":"Rose","age":"18"},
]

sendData = () => {
   for(let i=0; i<Data.length; i++) {
      doSetTimeout(
       ()=> {
          var myHeaders = new Headers();
          myHeaders.append("token", this.state.Token);
          myHeaders.append("Content-Type", "application/json");
          let Data = JSON.stringify(Data[i]);
          var requestOptions = {
            method: 'POST',
            headers: myHeaders,
            body: Data,
            redirect: 'follow'
          };
          fetch(sycnAddress + "Data", requestOptions)
            .then(response => response.json())
            .then((responseJson) => {
              console.log(responseJson);
              return responseJson;
            })
            .catch((error) => {
              console.log(error);
            });
       }
     , i*3000);
   }
}

我希望以3秒的间隔将数据一一发送到服务器但是此功能有问题，无法发送数据！

Answer 1

尝试在内部使用闭包单例函数

let Data = [
{"name":"John","age":"25"},
{"name":"Alex","age":"31"},
{"name":"Rose","age":"18"},
]

sendData = () => {
   for(let i=0; i<Data.length; i++) {

      (function(indx){

        setTimeout(function(){

        var myHeaders = new Headers();
          myHeaders.append("token", this.state.Token);
          myHeaders.append("Content-Type", "application/json");
          let Data = JSON.stringify(Data[i]);
          var requestOptions = {
            method: 'POST',
            headers: myHeaders,
            body: Data,
            redirect: 'follow'
          };
          fetch(sycnAddress + "Data", requestOptions)
            .then(response => response.json())
            .then((responseJson) => {
              console.log(responseJson);
              return responseJson;
            })
            .catch((error) => {
              console.log(error);
            });


        }, 3000 * indx);

      }(i));



   }
}

如何在doSetTimeout函数中执行几个命令？

1 个答案: