Question

我正在尝试将Microsoft Access数据库上传到Microsoft SQL Server Express数据库。

除主键名称外，Access和SQL数据库的结构相同。

错误代码：

System.InvalidOperationException: No data exists for the row/column. at System.Data.OleDb.OleDbDataReader.DoValueCheck(Int32 ordinal) at System.Data.OleDb.OleDbDataReader.GetValue(Int32 ordinal) at System.Data.OleDb.OleDbDataReader.get_Item(Int32 index) at ACCESStoMDF._Default.Button1_Click(Object sender, EventArgs e) in C:\Users\path2ACCESStoMDF\ACCESStoMDF\Default.aspx.cs:line 44

的web.config

<configuration>
  <connectionStrings>
    <add name="ACCESSdb"
     connectionString="Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\path1\DBaccess.accdb;Persist Security Info=False;" />
    <add name="MSSQLdb"
     connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\MSSQLdb.mdf;User Instance=true;"
     providerName="System.Data.SqlClient" />
  </connectionStrings>

MSAccessTOMSSQL.aspx.cs

    protected void Button1_Click(object sender, EventArgs e)
    {

        String connStr = ConfigurationManager.ConnectionStrings["ACCESSdb"].ConnectionString;
        String cmdStr = "SELECT * FROM [TableACCESS];";
        try
        {
            using (OleDbConnection conn = new OleDbConnection(connStr))
            {
                using (OleDbCommand cmd = new OleDbCommand(cmdStr, conn))
                {
                    conn.Open();
                    using (OleDbDataReader dr = cmd.ExecuteReader())
                    {

                        String connStr1 = ConfigurationManager.ConnectionStrings["MSSQLdb"].ConnectionString;
                        String cmdStr1 = "INSERT INTO [Table1] (col1,col2,col3) VALUES (@col1,@col2,@col3);";
                        try
                        {
                            using (SqlConnection conn1 = new SqlConnection(connStr1))
                            {
                                using (SqlCommand cmd1 = new SqlCommand(cmdStr1, conn1))
                                {
                                    conn1.Open();
                                    cmd1.Parameters.AddWithValue("@col1", dr[1]);
                                    cmd1.Parameters.AddWithValue("@col2", dr[2]);
                                    cmd1.Parameters.AddWithValue("@col3", dr[3]);
                                    cmd1.ExecuteNonQuery();
                                    conn1.Close();
                                    cmd1.Dispose();
                                    conn1.Dispose();
                                }
                            }
                        }
                        catch (Exception ex)
                        {
                            Label2.Text = "Insert Into: " + ex.ToString();
                        }
                    }
                    conn.Close();
                    cmd.Dispose();
                    conn.Dispose();
                }
            }
        }
        catch (Exception ex)
        {
            Label2.Text = "Access: " + ex.ToString();
        }
    }

Answer 1

OleDbDataReader允许您逐行处理SELECT查询的结果。如documentation所示，您需要执行类似

的操作

OleDbDataReader reader = command.ExecuteReader();

while (reader.Read())
{
    Console.WriteLine(reader[0].ToString());
}
reader.Close();

另请注意，返回行的数字索引从零开始，因此第一列为reader[0]。

将Microsoft Access数据库上载到Microsoft SQL Server Express数据库

1 个答案: