如何使用react native上传图片？

npm install -g react-native-cli

react-native init YourProjectName

cd YourProjectName
npm install react-native-image-picker axios

cd ios
pod install

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

import com.imagepicker.permissions.OnImagePickerPermissionsCallback;
import com.facebook.react.modules.core.PermissionListener;

public class MainApplication extends Application implements ReactApplication, OnImagePickerPermissionsCallback {
  private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
    // ...
    @Override
    protected List<ReactPackage> getPackages() {
      // ...
      new ImagePickerPackage(this), // 添加这一行
      // ...
    }
  };

  // ...

  @Override
  public void setPermissionListener(PermissionListener listener) {
    this.permissionListener = listener;
  }

  @Override
  public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    if (permissionListener != null && permissionListener.onRequestPermissionsResult(requestCode, permissions, grantResults)) {
      permissionListener = null;
    }
  }
}

import React, { useState } from 'react';
import { View, Button, Image } from 'react-native';
import ImagePicker from 'react-native-image-picker';
import axios from 'axios';

const App = () => {
  const [image, setImage] = useState(null);

  const selectImage = () => {
    ImagePicker.showImagePicker({}, (response) => {
      if (response.didCancel) {
        console.log('User cancelled image picker');
      } else if (response.error) {
        console.log('ImagePicker Error: ', response.error);
      } else {
        const source = { uri: response.uri };
        setImage(source);
        uploadImage(response);
      }
    });
  };

  const uploadImage = (response) => {
    const formData = new FormData();
    formData.append('image', {
      uri: response.uri,
      type: response.type,
      name: response.fileName
    });

    axios.post('YOUR_UPLOAD_URL', formData)
      .then((response) => {
        console.log('Upload success');
      })
      .catch((error) => {
        console.log('Upload error: ', error);
      });
  };

  return (
    <View>
      <Button title="Select Image" onPress={selectImage} />
      {image && <Image source={image} style={{ width: 200, height: 200 }} />}
    </View>
  );
};

export default App;

react-native run-android   // 运行Android应用
react-native run-ios       // 运行iOS应用