java - 当我想在 sqlite 表中插入一个值时，当我在 editText 中添加引号时，我的应用程序不断崩溃如何解决此问题？

Question

请帮助我，我不知道如何修复此错误

android.database.sqlite.SQLiteException: unrecognized token: "'''" (code 1): , while compiling: select * from Repository where itemName = '''
    at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)

这里是导致输入 Activity 和数据库hapler错误的代码

 final String query = "select * from Repository where itemName = '" + name + "'";
            if (mDataBase.getData(query).getCount() > 0) {....}

以及dbhalper中的代码

public Cursor getData(String sql) {
        SQLiteDatabase database = getReadableDatabase();
        return database.rawQuery(sql, null);
    }

Answer 1

名称似乎包含值'，这需要特殊处理并且需要为''，如下所示:-

A string constant is formed by enclosing the string in single quotes ('). A single quote within the string can be encoded by putting two single quotes in a row - as in Pascal. C-style escapes using the backslash character are not supported because they are not standard SQL. expression - Literal Values (Constants)

我相信如果您使用(如果没有参数则传递 null):-

public Cursor getData(String sql, String[] args) {
    SQLiteDatabase database = getReadableDatabase();
    return database.rawQuery(sql, args);
}

连同:-

final String query = "select * from Repository where itemName =?";
if (mDataBase.getData(query,new String[]{name}).getCount() > 0) {....}

? 将被替换为正确的值。