SqlCommand.ExecuteScalar法   执行查询，并返回   第一排的结果集中在返回的第一列   查询。其他列或行被忽略。

SqlCommand.ExecuteScalar Method Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

我想这将涉及大量使用非专利药。

I guess this will involve heavy use of generics.

假设我有一个 SQLiteDatabase /的光标对象。

Assume I have an SQLiteDatabase/Cursor object.

推荐答案

这逻辑为我工作：

public int ExecuteScalar(/* code...*/) {
    Cursor cursor = database.rawQuery(sql, selectionArgs);
    try {
        cursor.moveToNext();
        int val = cursor.getInt(0);
        cursor.close();
        return val;
    }   
    catch (Exception e) {
        /* code...*/
    }
    return -1;
}