如何对数据表中的项目进行通知循环并在dataGridView上显示实时值

Question

我有一个充满数据的DataTable，有称为“ ALIASNUM”和“ VALUE”的列。 我正在尝试获取“ ALIASNUM”列中所有项目的值，并将其放在“ VALUE”列中。

这是我的代码：

NDde.Client.DdeClient client = new NDde.Client.DdeClient("TR1EMCodeEmulator", "Command");
client.Connect();
DataRow[] rowList = dataTable1.Select("ALIASNUM > 0 ");
foreach (DataRow dr in rowList)
{
     string alias = dr["ALIASNUM"].ToString();
     string currentValue = client.Request(alias, 60000);
     dr["VALUE"] = currentValue;
}

这段代码运行良好，但是我想使用StartAdvise将这些值设置为实时值，并在dataGridView上显示具有实时值的数据表，我该怎么做？

---

这是使用startadvise之后的完整代码：

1-建议的处理程序

private void client1_Advise(Object sender, NDde.Client.DdeAdviseEventArgs e)
{
    DataRow[] rowList1 = dataTable1.Select("ALIASNUM = " + e.Item);
    if (rowList1.Length > 0)
    {
        rowList1[0]["VALUE"] = e.Text;
    }
}

2- DDE连接

string ddeApplication1 = "";
string ddeTopic1 = "";
ddeApplication1 = "TR1EMCodeEmulator";
ddeTopic1 = "Command";
NDde.Client.DdeClient client1 = new NDde.Client.DdeClient(ddeApplication1, ddeTopic1);
client1.Connect();

3- StartAdvise

//Get the values for the requested data through the DDE connections.
client1.Advise += client1_Advise;
DataRow[] rowList1 = dataTable1.Select("ALIASNUM > 0 ");
foreach (DataRow dr1 in rowList1)
    {
        string alias = dr1["ALIASNUM"].ToString();
        client1.StartAdvise(alias, 1, true, 60000);
    }

Answer 1

这是您重新设置的方法：

try
{
    NDde.Client.DdeClient client = new NDde.Client.DdeClient("TR1EMCodeEmulator", "Command");
    client.Connect();
    client.Advise += client_Advise;
    DataRow[] rowList = dataTable1.Select("ALIASNUM > 0 ");
    foreach (DataRow dr in rowList)
          client.StartAdvise(dr["ALIASNUM"] as String, 0, true, 60000);  //the zero is DDE type, replace as necessary
}
catch (Exception ex)
{
    //Do what you need to here...
}

这是一个建议的处理程序：

private void client_Advise(Object sender, NDde.Client.DdeAdviseEventArgs e)
{
    //Tests to consider:  Is it the right format?  Is it valid?  What's the state?

    DataTable dt = new DataTable();  //replace with whatever data you *really are updating*
    DataRow[] row = dt.Select("ALIASNUM = " + e.Item);
    if (row.Length > 0)
        row[0]["VALUE"] = e.Text;  //could use e.Data and convert from Byte[] to what you need (what is VALUE type?)
}

其他注意事项：

1）如果dataTable1通过SQL调用导出，这将是缓慢的。

2）您将受到网格刷新的支配，因此请在需要时进行处理。

3）总是考虑类型。 DDE正在发送类型信息和原始字节……请尽可能使用它。