android - 标题的值无法从 ReadablenativeMap 转换为字符串

Question

考虑:

InsertDataToServer = () => {
  const { pinValue1 } = this.state;
  const { pinValue2 } = this.state;
  const { pinValue3 } = this.state;
  const { pinValue4 } = this.state;
  var String_3 = pinValue1.concat(" ", pinValue2);
  var String_4 = String_3.concat(" " , pinValue3);
  var String_5 = String_4.concat(" " , pinValue4);

  fetch("http://www.aonde.biz/mobile/doLogin.php", {
    method: "POST",
    headers: {
      Accept: "application/json",
      "Content-Type": "application/json"
    },
    body: JSON.stringify({
      "pin": 212,
    })
  })
    .then(response => response.json())
    .then(responseJson => {
      // Showing the response message coming from
      // the server after inserting records.
      Alert.alert(responseJson);
    })
    .catch(error => {
      console.error(error);
    });

在上面的代码中，当我传递“pin”参数API时，它显示了这个错误:

我该如何解决这个问题？

Answer 1

当代码更改为:

Alert.alert('错误:', 错误)

到:

Alert.alert('错误:', error.message)