This print for content only-size & color not accurate 7" X 9-1/4" / casebound / malloy

// Allow user to select an assembly to load.

OpenFileDialog dlg = new OpenFileDialog();

if (dlg.ShowDialog() == DialogResult.OK)

{

if(dlg.FileName.Contains("CommonSnappableTypes"))

MessageBox.Show("CommonSnappableTypes has no snap-ins!");

else if(!LoadExternalModule(dlg.FileName))

MessageBox.Show("Nothing implements IAppFunctionality!");

}

}

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8849CH16.qxd  10/9/07  4:27 PM  Page 556

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The LoadExternalModule() method performs the following tasks:

• Dynamically loads the selected assembly into memory

• Determines whether the assembly contains any types implementing IAppFunctionality

• Creates the type using late binding

If a type implementing IAppFunctionality is found, the DoIt() method is called, and the fully

qualified name of the type is added to the ListBox (note that the foreach loop will iterate over all

types in the assembly to account for the possibility that a single assembly has multiple snap-ins).

Finally, notice that we are making use of a LINQ query to obtain IAppFunctionality-compatible

class types.

private bool LoadExternalModule(string path)

{

bool foundSnapIn = false;

Assembly theSnapInAsm = null;

try

{