c# - Unity Android MySQL连接功能失败：索引超出数组范围

问题描述

我有一个类来处理客户端和数据库（MySQL）之间的所有数据库交互（我知道并理解我不应该允许直接访问数据库）

public T getDatabaseValue<T>(string value, string query)
{
    try
    {
        connection = new MySqlConnection(connectionString);
        connection.Open();
        command = new MySqlCommand(query, connection);
        MySqlDataReader reader = command.ExecuteReader();
        if (reader.Read())
        {
            return (T)reader[value];
        }
        else
            return default(T);
    }
    catch (MySqlException SQLex)
    {
        Debug.Log("Database get failed (SQL Exception), query: " + query);
        Debug.Log("Exception Message: " + SQLex.Message);   
        return default(T);
    }
    catch (System.Exception ex)
    {
        Debug.Log("Database get failed (System Exception), query: " + query);
        Debug.Log("Exception Message: " + ex.Message);
        return default(T);
    }
}

这在编辑器中完美无缺。在 Android 上构建和运行时，我通过 Monitor 收到此错误消息：

01-01 15:21:14.141: I/Unity(23761): (Filename: ./Runtime/Export/Debug.bindings.h Line: 43)
01-01 15:21:14.829: I/Unity(23761): Database get failed (System Exception), query: SELECT MAX(DT_Stamp) FROM tbl_Store;
01-01 15:21:14.829: I/Unity(23761):  
01-01 15:21:14.829: I/Unity(23761): (Filename: ./Runtime/Export/Debug.bindings.h Line: 43)
01-01 15:21:14.829: I/Unity(23761): Exception Message: Index was outside the bounds of the array.

我没有使用数组来存储阅读器的内容，这是调用此示例的行（它发生在所有数据库交互中，不仅仅是这个，而且不仅仅是这个数据库查询函数）：

    DateTime DB_Date = getDatabaseValue<DateTime>("MAX(DT_Stamp)", "SELECT MAX(DT_Stamp) FROM tbl_Store;");

这是 tbl_Store 的内容：

(Item_ID (int)), (Item_Name (varchar)), (Item_Price (float)), (In_Use (bit)), (DT_Stamp (datetime))

4 Hero Upgrade #1 100 1 2018-12-11 09:53:14 
5 Hero Upgrade #2 300 1 2018-12-11 09:53:14 
6 Hero Upgrade #3 700 1 2018-12-11 09:53:14

我还在一个更基本的项目中尝试了它，以获取 Android 返回的核心错误消息：

01-01 17:23:48.307: E/Unity(10476): IndexOutOfRangeException: Index was outside the bounds of the array. 
01-01 17:23:48.307: E/Unity(10476): at System.Diagnostics.TraceInternal.get_AppName () [0x0000e] in <ac210d81537245bc838518cc8e845861>:0 
01-01 17:23:48.307: E/Unity(10476): at System.Diagnostics.TraceInternal.TraceEvent (System.Diagnostics.TraceEventType eventType, System.Int32 id, System.String format, System.Object[] args) [0x0003d] in <ac210d81537245bc838518cc8e845861>:0 
01-01 17:23:48.307: E/Unity(10476): at System.Diagnostics.Trace.TraceError (System.String message) [0x00000] in <ac210d81537245bc838518cc8e845861>:0 
01-01 17:23:48.307: E/Unity(10476): at MySql.Data.MySqlClient.MySqlTrace.LogError (System.Int32 id, System.String msg) [0x00028] in <326e9aab93854e739606c3572c385a34>:0 
01-01 17:23:48.307: E/Unity(10476): at MySql.Data.MySqlClient.MySqlPool.TryToGetDriver () [0x00031] in <326e9aab93854e739606c3572c385a34>:0 
01-01 17:23:48.307: E/Unity(10476): at MySql.Data.MySqlClient.MySqlPool.GetConnection () [0x0001c] in <326e9aab93854e739606c3572c385a34>:0 
01-01 17:23:48.307: E/Unity(10476): at MySql.Data.MySqlClient.MySqlConnection.Open () [0x000f3] in <326e9aab93854e739606c3572c385a34>:0 
01-01 17:23:48.307: E/Unity(10476): at texttest1.Start () [0x00011] in <dd75ac8e3f854a97ac132dae6ec658fd>:0

我可能在这里遗漏了一些非常简单的东西，但任何帮助将不胜感激！

标签： c#mysql.netvisual-studiounity3d

c# - Unity Android MySQL连接功能失败：索引超出数组范围

问题描述

解决方案

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