C＃WinForm应用程序中的System.IO.FileLoadException

Question

我试图在我的C＃WinForm应用程序中实现SQLite数据库，因为我引用this post但是我在将记录插入数据库时​​遇到以下错误

我的数据库助手类代码是 -

class SQLiteDatabase
{
    String dbConnection;

    /// <summary>
    ///     Default Constructor for SQLiteDatabase Class.
    /// </summary>
    public SQLiteDatabase()
    {
        dbConnection = "Data Source=test_db.s3db";
    }

    /// <summary>
    ///     Single Param Constructor for specifying the DB file.
    /// </summary>
    /// <param name="inputFile">The File containing the DB</param>
    public SQLiteDatabase(String inputFile)
    {
        dbConnection = String.Format("Data Source={0}", inputFile);
    }

    /// <summary>
    ///     Single Param Constructor for specifying advanced connection options.
    /// </summary>
    /// <param name="connectionOpts">A dictionary containing all desired options and their values</param>
    public SQLiteDatabase(Dictionary<String, String> connectionOpts)
    {
        String str = "";
        foreach (KeyValuePair<String, String> row in connectionOpts)
        {
            str += String.Format("{0}={1}; ", row.Key, row.Value);
        }
        str = str.Trim().Substring(0, str.Length - 1);
        dbConnection = str;
    }

    /// <summary>
    ///     Allows the programmer to run a query against the Database.
    /// </summary>
    /// <param name="sql">The SQL to run</param>
    /// <returns>A DataTable containing the result set.</returns>
    public DataTable GetDataTable(string sql)
    {
        DataTable dt = new DataTable();
        try
        {
            SQLiteConnection cnn = new SQLiteConnection(dbConnection);
            cnn.Open();
            SQLiteCommand mycommand = new SQLiteCommand(cnn);
            mycommand.CommandText = sql;
            SQLiteDataReader reader = mycommand.ExecuteReader();
            dt.Load(reader);
            reader.Close();
            cnn.Close();
        }
        catch (Exception e)
        {
            throw new Exception(e.Message);
        }
        return dt;
    }

    /// <summary>
    ///     Allows the programmer to interact with the database for purposes other than a query.
    /// </summary>
    /// <param name="sql">The SQL to be run.</param>
    /// <returns>An Integer containing the number of rows updated.</returns>
    public int ExecuteNonQuery(string sql)
    {
        SQLiteConnection cnn = new SQLiteConnection(dbConnection);
        cnn.Open();
        SQLiteCommand mycommand = new SQLiteCommand(cnn);
        mycommand.CommandText = sql;
        int rowsUpdated = mycommand.ExecuteNonQuery();
        cnn.Close();
        return rowsUpdated;
    }

    /// <summary>
    ///     Allows the programmer to retrieve single items from the DB.
    /// </summary>
    /// <param name="sql">The query to run.</param>
    /// <returns>A string.</returns>
    public string ExecuteScalar(string sql)
    {
        SQLiteConnection cnn = new SQLiteConnection(dbConnection);
        cnn.Open();
        SQLiteCommand mycommand = new SQLiteCommand(cnn);
        mycommand.CommandText = sql;
        object value = mycommand.ExecuteScalar();
        cnn.Close();
        if (value != null)
        {
            return value.ToString();
        }
        return "";
    }


    /// <summary>
    ///     Allows the programmer to easily insert into the DB
    /// </summary>
    /// <param name="tableName">The table into which we insert the data.</param>
    /// <param name="data">A dictionary containing the column names and data for the insert.</param>
    /// <returns>A boolean true or false to signify success or failure.</returns>
    public bool Insert(String tableName, Dictionary<String, String> data)
    {
        String columns = "";
        String values = "";
        Boolean returnCode = true;
        foreach (KeyValuePair<String, String> val in data)
        {
            columns += String.Format(" {0},", val.Key.ToString());
            values += String.Format(" '{0}',", val.Value);
        }
        columns = columns.Substring(0, columns.Length - 1);
        values = values.Substring(0, values.Length - 1);
        try
        {
            // Getting Error Here               
            this.ExecuteNonQuery(String.Format("insert into {0}({1}) values({2});", tableName, columns, values));
        }
        catch (Exception fail)
        {
            MessageBox.Show(fail.Message);
            returnCode = false;
        }
        return returnCode;
    }
}

我在以下行的 插入功能 中遇到异常 -

this.ExecuteNonQuery(String.Format("insert into {0}({1}) values({2});", tableName, columns, values));

我已在项目的根目录中创建了我的数据库文件（即test_db.s3db）。 谢谢..！

Answer 1

您可以在应用配置中通过添加以下xml来配置：

<startup useLegacyV2RuntimeActivationPolicy="true">
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
<requiredRuntime version="v4.0.20506" />
</startup>

在这个link中，你会得到更多关于此的信息。