无法以读/写模式打开数据库 [英] Not able to open database in read/write mode

问题描述

我遇到以下错误:

不是错误(代码0):无法以读写模式打开数据库.

not an error (code 0): Could not open the database in read/write mode.

我已添加

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

我正在尝试在SD卡中存在的数据库中输入数据，我能够通过"OPEN_READONLY"读取数据库中已存在的数据.使用"OPEN_READWRITE"时出现错误

I am trying to enter data in the database that is present in the SD card, I am able to read the data that is already present in the database through "OPEN_READONLY". I am getting error when using "OPEN_READWRITE"

推荐答案

您的问题不清楚，但我会尽力回答.

Your question is not that clear, but I'll try to answer.

您的数据库很可能是

1. 尚不存在，您必须创建它；
2. 您的数据库文件是只读的，您必须进行更改(

1. Don't exist yet, and you have to create it;
2. Your database file is read only, you have to change it (This question might be related).

对于#2，而不是使用 ，请使用 SQLiteOpenHelper#getWritableDatabase

For #2, instead of using SQLiteOpenHelper#getReadableDatabase(), use SQLiteOpenHelper#getWritableDatabase

如果您的数据库位于外部存储单元上，则还需要检查其他几件事:

If your database is on an external storage unit, you have a few other things to check:

1. 当前是否已安装外部存储?如果没有，您将无法访问数据库.
2. 是否将其安装为只读?如果是这样，则必须对此进行更改.
3. 您检查过路径了吗?正确吗?

问题可能出在任何这些主题上.

The problem might be on any of those topics.

要检查它是否以只读方式安装，请尝试以下操作:

To check if it's mounted as read-only, try the following:

/* Checks if external storage is available for read and write */
public boolean isExternalStorageWritable() {
    String state = Environment.getExternalStorageState();
    if (Environment.MEDIA_MOUNTED.equals(state)) {
        return true;
    }
    return false;
}

/* Checks if external storage is available to at least read */
public boolean isExternalStorageReadable() {
    String state = Environment.getExternalStorageState();
    if (Environment.MEDIA_MOUNTED.equals(state) ||
        Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
        return true;
    }
    return false;
}

来自此处.

有关Environment类的更多信息，请参阅文档.

For more info on the Environment class, please refer to the docs.

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