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如何對數據表中的項目進行通知循環並在dataGridView上顯示實時值

[英]how to make Advise loop for items in a DataTable and show realtime values on dataGridView

我有一個充滿數據的DataTable,有稱為“ ALIASNUM”和“ VALUE”的列。 我正在嘗試獲取“ ALIASNUM”列中所有項目的值,並將其放在“ VALUE”列中。

這是我的代碼:

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;
}

這段代碼運行良好,但是我想使用StartAdvise將這些值設置為實時值,並在dataGridView上顯示具有實時值的數據表,我該怎么做?


這是使用startadvise之后的完整代碼:

1-建議的處理程序

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連接

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);
    }

這是您重新設置的方法:

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...
}

這是一個建議的處理程序:

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?)
}

其他注意事項:

1)如果dataTable1通過SQL調用導出,這是緩慢的。

2)您將受到網格刷新的支配,因此請在需要時進行處理。

3)總是考慮類型。 DDE正在發送類型信息和原始字節……請盡可能使用它。

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