Question

I have Silverlight application that retrieves data from the database through a WCF Service. What my application have to do is to display the referent data anytime a button gets MouseOvered. I did it in a way that that when a button gets MouseOvered, I called my service and retrieved the data, but it generetad a big delay. Now, I think that another way should be making a list of all objects from the table, and just searching the id in the list when the action is triggered. I started coding, but it resulted in fail (and such an ugly piece of code).

My Working Code

private void MouseOverHarbor(object sender, RoutedEventArgs e)
{
    Ellipse thisPath = (Ellipse)sender;
    DataRetrieverReference.DataRetrieverClient webService = new DataRetrieverReference.DataRetrieverClient();
    webService.GetDataCompleted += new EventHandler<DataRetrieverReference.GetDataCompletedEventArgs>(webService_GetDataCompleted);
    webService.GetDataAsync(Convert.ToInt32(thisPath.DataContext));
}

void webService_GetDataCompleted(object sender, WebPortos.DataRetrieverReference.GetDataCompletedEventArgs e)
{
    NameField.Text = e.Result.Name;
    CityField.Text = e.Result.City;
    StateField.Text = e.Result.State;
    CompanyField.Text = e.Result.Company;
}

What I tried to do

private List<vwPortos_SEP> harborList;
private int counter;

public Brasil()
{
    InitializeComponent();
    this.harborList = new List<vwPortos_SEP>();

    DataRetrieverClient webService = new DataRetrieverClient();
    webService.GetCounterCompleted += new EventHandler<GetCounterCompletedEventArgs>(webService_GetCounterCompleted);
    webService.GetCounterAsync();
    webService.GetDataCompleted += new EventHandler<DataRetrieverReference.GetDataCompletedEventArgs>(webService_GetDataCompleted);

    for (int i = 0; i < counter; i++)
    {                                
        webService.GetDataAsync(i);
    }               

}

void webService_GetDataCompleted(object sender, WebPortos.DataRetrieverReference.GetDataCompletedEventArgs e)
{
    MessageBox.Show("It works!");//It doesn't work!
    try
    {
        this.harborList.Add(e.Result);
    }
    catch (Exception exc)//It doesn't even throw ecxpetions, this method is never reached.
    {
        MessageBox.Show(exc.Message);
        MessageBox.Show(exc.InnerException.Message);
    }
}

Maybe I’m missing something really big, but my webService_GetDataCompleted method is never reached.

Thanks in advance folks!

Answer 1

Is this call:

webService.GetCounterAsync();

used to set counter?

If so you’re not letting it finish before looping with counter as the termination value. It’s highly likely that counter is still 0 so your GetDataAsync calls aren’t happening.

for (int i = 0; i < counter; i++)
{                                
    webService.GetDataAsync(i);
}

Move this code into your webService_GetCounterCompleted method, so your code becomes:

public Brasil()
{
    InitializeComponent();
    this.harborList = new List<vwPortos_SEP>();

    DataRetrieverClient webService = new DataRetrieverClient();
    webService.GetCounterCompleted +=
        new EventHandler<GetCounterCompletedEventArgs>(webService_GetCounterCompleted);
    webService.GetCounterAsync();
}

void webService_GetCounterCompleted(object sender,
         WebPortos.DataRetrieverReference.GetCounterCompletedEventArgs e)
{
    webService.GetDataCompleted +=
     new EventHandler<DataRetrieverReference.GetDataCompletedEventArgs>(webService_GetDataCompleted);

    for (int i = 0; i < counter; i++)
    {                                
        webService.GetDataAsync(i);
    }
}

Plus your existing webService_GetDataCompleted method.