Accessing the dbf file

[Thomas]

Is it possible to access the dbf file during the binding (see below):

this

 

 

.StateLayer.Reader.DataSource = new Uri(string.Format(ShapeRelativeUriFormat, "usa_states.dbf"), UriKind.Relative);

I would like to append some text to each of the state names, if I could do some sort of loop / foreach that would be great. Can you provide sample code?

Regards
Thomas

 

 

 

[Andrey]

Hi Thomas,

When the shape reader reads the shape file (shp and dbf pair) then it creates the ExtendedData instance for each shape with a data from dbf file.
You can change values of properties the ExtendedData provides. Also you can add new property and then assign the value from any other source.
You can make it from a code for each read shape using the PreviewReadCompleted event. It occurs before the shapes are added to the information layer.
The sample code is below.

private const string NonDbfDataField = "SampleDataField";

void RadMap1_InitializeCompleted(object sender, EventArgs e)
{
    if (!this.initialized)
    {
        this.initialized = true;

        this.StateLayer.Reader = new MapShapeReader();
        this.StateLayer.Reader.PreviewReadCompleted += new PreviewReadShapesCompletedEventHandler(Reader_PreviewReadCompleted);

        this.StateLayer.Reader.Source = new Uri(string.Format(ShapeRelativeUriFormat, "usa_states.shp"), UriKind.Relative);
        this.StateLayer.Reader.DataSource = new Uri(string.Format(ShapeRelativeUriFormat, "usa_states.dbf"), UriKind.Relative);
    }
}

private void Reader_PreviewReadCompleted(object sender, PreviewReadShapesCompletedEventArgs eventArgs)
{
    if (eventArgs.Error == null)
    {
        foreach (MapShape shape in eventArgs.Items)
        {
            this.SetAdditionalData(shape);
        }
    }
}

private void SetAdditionalData(MapShape shape)
{
    ExtendedData extendedData = shape.ExtendedData;
    if (extendedData != null)
    {
        // add new property to ExtendedData
        if (!extendedData.PropertySet.ContainsKey(NonDbfDataField))
        {
            extendedData.PropertySet.RegisterProperty(NonDbfDataField, "", typeof(string), "");
        }

        string stateName = (string)shape.ExtendedData.GetValue("STATE_NAME");
        string additionalFieldValue = this.GetDataByStateName(stateName);

        // assign value to new property
        shape.ExtendedData.SetValue(NonDbfDataField, additionalFieldValue);

        // change existing property
        shape.ExtendedData.SetValue("STATE_NAME", "State name: " + (string)shape.ExtendedData.GetValue("STATE_NAME"));
    }
}

private string GetDataByStateName(string stateName)
{
    // returns additional field value
}

Greetings,
Andrey Murzov
the Telerik team