RN获取blob坏base64-仅安卓系统问题

Question

我在react native中遇到一个问题，我从API下载了一个基本64字符串，并在移动设备上将其呈现为PDF。

该项目是用React原生构建的-代码在iOS上运行良好，但在Android上，我们收到了一个"坏的base64"/无效的PDF格式错误。

代码：

//fetch on button click
getBill = () => {
if (Platform.OS === "android") {
this.getAndroidPermission();
} else {
this.downloadBill();
}
};
//check user has permissions on device (only for android)
getAndroidPermission = async () => {
try {
const granted = await PermissionsAndroid.request(
PermissionsAndroid.PERMISSIONS.WRITE_EXTERNAL_STORAGE
);
const grantedRead = await PermissionsAndroid.request(
PermissionsAndroid.PERMISSIONS.READ_EXTERNAL_STORAGE
);
if (
granted === PermissionsAndroid.RESULTS.GRANTED &&
grantedRead === PermissionsAndroid.RESULTS.GRANTED
) {
this.downloadBill();
} else {
Alert.alert(
"Permission Denied!",
"You need to give storage permission to download the file"
);
}
} catch (err) {
console.warn(err);
}
};
//download and display bill
downloadBill = async () => {
this.setState({ loading: true });
let billId = this.state.billId;
let user = await AsyncStorage.getItem("user");
let parseUser = JSON.parse(user);
let userToken = parseUser.token;
RNFetchBlob.config({
addAndroidDownloads: {
useDownloadManager: true,
notification: true,
path:
RNFetchBlob.fs.dirs.DownloadDir +
"/" +
`billID_${this.state.billId}.pdf`,
mime: "application/pdf",
description: "File downloaded by download manager.",
appendExt: "pdf",
trusty: true,
},
})
.fetch("GET", `${config.apiUrl}/crm/getbillfile/${billId}`, {
Authorization: "Bearer " + userToken,
})
.then((resp) => {
let pdfLocation =
RNFetchBlob.fs.dirs.DocumentDir +
"/" +
`billID_${this.state.billId}.pdf`;
RNFetchBlob.fs.writeFile(pdfLocation, resp.data, "base64");
FileViewer.open(pdfLocation, {
onDismiss: () => this.setState({ loading: false }),
});
});
}; 

Android清单：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.DOWNLOAD_WITHOUT_NOTIFICATION" /> 
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
<action android:name="android.intent.action.DOWNLOAD_COMPLETE"/>
</intent-filter>

如有任何帮助，将不胜感激

Answer 1

您在android中打开的文件路径错误，而在IOS中，它实际上保存在正确的位置并从正确的位置打开。

打开文件之前请检查操作系统，然后再打开文件。

....
const fpath = `${RNFetchBlob.fs.dirs.DownloadDir}${filename}`;
RNFetchBlob.config({
addAndroidDownloads: {
useDownloadManager: true,
notification: true,
path: fpath,
description: "File downloaded by download manager.",
},
})
.fetch("GET", `${config.apiUrl}/crm/getbillfile/${billId}`, {
Authorization: "Bearer " + userToken,
})
.then((resp) => {
if (OS == "ios") {
// ... do existing logic    
} else if (OS === "android") {
// FileViewer or RNFetchBlob should work.
RnFetchBlob.android.actionViewIntent(fpath, "application/pdf");
}
});
};