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CachedDataItem.DataType Property

Gets or sets the assembly-qualified name of the type of the cached data object.

Namespace:  Microsoft.VisualStudio.Tools.Applications
Assembly:  Microsoft.VisualStudio.Tools.Applications.ServerDocument (in Microsoft.VisualStudio.Tools.Applications.ServerDocument.dll)

Syntax

'Declaration
Public Property DataType As String
public string DataType { get; set; }

Property Value

Type: System.String
The assembly-qualified name of the type of the cached data object.

Remarks

The DataType property returns an assembly-qualified name of the cached data type that is useful for creating a new instance of a custom type that is in the data cache. For example, you can get the Type of a custom data type by passing the assembly-qualified type name to the GetType method. You can then create an instance of the custom type by passing this Type as a parameter to the Activator.CreateInstance method.

For details about the format of the assembly-qualified type string that is returned by the DataType property, see the Type.AssemblyQualifiedName property.

Examples

The following code example uses the SerializeDataInstance method to modify the value of a string that is cached in a worksheet of an Excel workbook. The code uses the DataType property to verify that the cached data object is a string before trying to modify it.

This example requires:

  • A document-level customization for Excel that has a Sheet1 class in the ExcelWorkbook1 namespace, and a cached string in the Sheet1 class named CachedString.

  • A console application project or some other non-Office project.

  • References to the following assemblies:

    • Microsoft.VisualStudio.Tools.Applications.ServerDocument.dll

    • Microsoft.VisualStudio.Tools.Applications.Runtime.dll

  • Imports (for Visual Basic) or using (for C#) statements for Microsoft.VisualStudio.Tools.Applications and Microsoft.VisualStudio.Tools.Applications.Runtime namespaces at the top of your code file.

Private Sub ModifyCachedString(ByVal documentPath As String)
    Dim runtimeVersion As Integer = 0
    Dim serverDocument1 As ServerDocument = Nothing 

    Try
        runtimeVersion = ServerDocument.GetCustomizationVersion(documentPath)
        If runtimeVersion <> 3 Then
            MessageBox.Show("This document does not have a Visual Studio Tools for Office " & _
                "customization, or it has a customization that was created with a version of " & _
                "the runtime that is incompatible with this version of the ServerDocument class.")
            Return 
        End If 

        If ServerDocument.IsCacheEnabled(documentPath) Then
            serverDocument1 = New ServerDocument(documentPath)
            Dim hostItem1 As CachedDataHostItem = _
                serverDocument1.CachedData.HostItems("ExcelWorkbook1.Sheet1")
            Dim dataItem1 As CachedDataItem = hostItem1.CachedData("CachedString")

            If dataItem1 IsNot Nothing AndAlso _
                Type.GetType(dataItem1.DataType).Equals(GetType(String)) Then

                dataItem1.SerializeDataInstance("This is the new cached string value.")
                serverDocument1.Save()
            End If 
        Else
            MessageBox.Show("The specified document does not have cached data.")
        End If 

    Catch ex As System.IO.FileNotFoundException
        System.Windows.Forms.MessageBox.Show("The specified document does not exist.")
    Catch ex As UnknownCustomizationFileException
        System.Windows.Forms.MessageBox.Show("The specified document has a file " & _
            "extension that is not supported by Visual Studio Tools for Office.")
    Finally 
        If Not (serverDocument1 Is Nothing) Then
            serverDocument1.Close()
        End If 
    End Try 
End Sub
private void ModifyCachedString(string documentPath)
{
    int runtimeVersion = 0;
    ServerDocument serverDocument1 = null;

    try
    {
        runtimeVersion = ServerDocument.GetCustomizationVersion(documentPath);

        if (runtimeVersion != 3)
        {
            MessageBox.Show("This document does not have a Visual Studio Tools for " +
                "Office customization, or it has a customization that was created with " +
                "a version of the runtime that is incompatible with this version of the " +
                "ServerDocument class.");
            return;
        }

        if (ServerDocument.IsCacheEnabled(documentPath))
        {
            serverDocument1 = new ServerDocument(documentPath);
            CachedDataHostItem hostItem1 = 
                serverDocument1.CachedData.HostItems["ExcelWorkbook1.Sheet1"];
            CachedDataItem dataItem1 = hostItem1.CachedData["CachedString"];

            if (dataItem1 != null &&
                Type.GetType(dataItem1.DataType) == typeof(string))
            {
                dataItem1.SerializeDataInstance("This is the new cached string value.");
                serverDocument1.Save();
            }
        }
        else
        {
            MessageBox.Show("The specified document does not have cached data.");
        }
    }
    catch (System.IO.FileNotFoundException)
    {
        System.Windows.Forms.MessageBox.Show("The specified document does not exist.");
    }
    catch (UnknownCustomizationFileException)
    {
        System.Windows.Forms.MessageBox.Show("The specified document has a file " +
            "extension that is not supported by Visual Studio Tools for Office.");
    }
    finally
    {
        if (serverDocument1 != null)
            serverDocument1.Close();
    }
}

.NET Framework Security

See Also

Reference

CachedDataItem Class

Microsoft.VisualStudio.Tools.Applications Namespace