C# 数据库插入 (ASP.NET) - ExecuteNonQuery：CommandText 属性尚未初始化

Question

我第一次从 ASP.NET/C# 进行插入时遇到了一个小问题。每次运行此代码时，我都会收到以下错误：“ ExecuteNonQuery：CommandText 属性尚未初始化” 有谁知道这是什么意思以及我如何解决它？

提前致谢！

string sqlQuery = "INSERT INTO ATI_LOG_IO (Date, Connect_Time, Disconnect_Time, ATI_Rep, Reason_For_Access, Property_Contact, Case_Number, Comments, Property_ID)";
sqlQuery += "VALUES (@Today, @Connect, @Disconnect, @Rep, @Reason, @Contact, @CaseNum, @Comments, @PropertyID)";
using (SqlConnection dataConnection = new SqlConnection(connectionString))
{
    using (SqlCommand dataCommand = dataConnection.CreateCommand())
    {
        dataConnection.Open();
        dataCommand.CommandType = CommandType.Text;
        dataCommand.CommandText = sqlQuery;
        dataCommand.Parameters.Add("@Today", DateTime.Today.ToString());
        dataCommand.Parameters.Add("@Connect", txtInDate.Text + " " + fromHrs.Text + ":" + fromMins.Text + ":00");
        dataCommand.Parameters.Add("@Disconnect", txtOutdate.Text + " " + toHrs.Text + ":" + fromMins.Text + ":00");
        dataCommand.Parameters.Add("@Rep", repID);
        dataCommand.Parameters.Add("@Reason", txtReason.Text);
        dataCommand.Parameters.Add("@Contact", txtContact.Text);
        dataCommand.Parameters.Add("@CaseNum", txtCaseNum.Text);
        dataCommand.Parameters.Add("@Comments", txtComments.Text);
        dataCommand.Parameters.Add("@PropertyID", lstProperties.SelectedValue);
        dataCommand.ExecuteNonQuery();
        dataConnection.Close();
    }
}

Answer 1

string sqlQuery = "INSERT INTO ATI_LOG_IO (Date, Connect_Time, Disconnect_Time, ATI_Rep, Reason_For_Access, Property_Contact, Case_Number, Comments, Property_ID)";
sqlQuery += " VALUES (@Today, @Connect, @Disconnect, @Rep, @Reason, @Contact, @CaseNum, @Comments, @PropertyID)";
using (SqlConnection dataConnection = new SqlConnection(connectionString))
{
    using (SqlCommand dataCommand = new SqlCommand(sqlQuery, dataConnection))
    {
        dataCommand.Parameters.AddWithValue("Today", DateTime.Today.ToString());
        dataCommand.Parameters.AddWithValue("Connect", txtInDate.Text + " " + fromHrs.Text + ":" + fromMins.Text + ":00");
        dataCommand.Parameters.AddWithValue("Disconnect", txtOutdate.Text + " " + toHrs.Text + ":" + fromMins.Text + ":00");
        dataCommand.Parameters.AddWithValue("Rep", repID);
        dataCommand.Parameters.AddWithValue("Reason", txtReason.Text);
        dataCommand.Parameters.AddWithValue("Contact", txtContact.Text);
        dataCommand.Parameters.AddWithValue("CaseNum", txtCaseNum.Text);
        dataCommand.Parameters.AddWithValue("Comments", txtComments.Text);
        dataCommand.Parameters.AddWithValue("PropertyID", lstProperties.SelectedValue);

        dataConnection.Open();
        dataCommand.ExecuteNonQuery();
        dataConnection.Close();
    }
}

复制粘贴就可以了

Answer 2

这通常意味着您没有设置 CommandText 属性，但在您的情况下，您已经设置了。

您应该尝试测试该行的 sqlQuery 字符串实际上不为空：

dataCommand.CommandText = sqlQuery;

附：作为“最佳实践”，您可能需要考虑在设置 SqlCommand 对象之后打开连接，以最大限度地减少打开连接所花费的时间：

    dataCommand.CommandType = CommandType.Text;
    dataCommand.CommandText = sqlQuery;
    dataCommand.Parameters.Add("@Today", DateTime.Today.ToString());
    //...
    dataConnection.Open();
    dataCommand.ExecuteNonQuery();
    dataConnection.Close();

Answer 3

查看您的字符串 sql 查询，您不会在“INTO”部分和“VALUES”部分之间留下空格。

...............Property_ID)";
sqlQuery += "VALUES (@Today, ..............

应该是：

...............Property_ID)";
sqlQuery += " VALUES (@Today, ..............