PRB: Executing Quit Method on OLE Object Quits VFP

ID: Q156751

The information in this article applies to:

Microsoft Visual FoxPro for Windows, versions 5.0, 6.0

SYMPTOMS

When you reference the Application property to Quit an OLE object, Visual FoxPro terminates. This article illustrates how to remove or hide an OLE Chart object and explains how the Application property behaves with OLE objects.

CAUSE

Each Visual FoxPro object has an Application property that refers to the Visual FoxPro application object. Because that object has a Quit method, invoking that method terminates the Visual FoxPro session.

The Application property refers to the Visual FoxPro object, not the object in the OLE control. The Help file topic concerning the Application Property states:

Provides a reference to the Application object containing an object.

In this case, the Application object is Visual FoxPro.

WORKAROUND

Since an Excel chart object does not have a Quit property, you must use properties available in Visual FoxPro. First, if you want to remove the object from the form, call the RemoveObject method of the form. For example:


   frmMyForm.RemoveObject('oletest')

This removes the object from the form without quitting Visual FoxPro.

Second, if you simply need to hide the OLE object, set the Visible property of the object to false (.F.). For example:


   frmMyForm.oletest.Visible=.T.

The method you choose depends on whether you need to access the OLEContainer again. Toggling the Visible property between True and False is faster than invoking the AddObject method. However, if you truly want to remove the object from the form, the RemoveObject method is preferable.

STATUS

This behavior is by design.

MORE INFORMATION

In the example below, you want to remove the Excel chart from the form. However, the command in step 2 causes the following error:

OLE IDispatch exception code 1000 from Microsoft Excel: Chart does not have Quit property.

As the error states, the object referenced, the Excel chart, does not have a Quit property. By adding the Application property to the command, no error occurs and Visual FoxPro closes. Since the Application property refers to Visual FoxPro and not Excel, the program exits Visual FoxPro.

The Object Browser application in Excel provides information on the properties available for use with Excel objects.

Steps to Reproduce Behavior

Create a program containing the following code and then execute it:


   PUBLIC frmMyForm
   frmMyForm = CREATEOBJECT("form")
   frmMyForm.AddObject("oleTest","OLEControl","Excel.Chart")
   frmMyForm.oletest.Visible=.t.
   frmMyForm.oletest.Height=115
   frmMyForm.Show

In the Command window, type:
```
   frmMyForm.oletest.Quit 
```

Click OK in the error box, and then type:
```
   frmMyForm.oletest.Application.Quit 
```

REFERENCES

For more information about properties and methods available to the Application Object, search for "Application Object" and then "Properties" or "Methods" in the Visual FoxPro Help file. Also see the following articles in the Microsoft Knowledge Base:

Q156548 How To Use the object Property to Reference Methods/Properties

Q155747 How To Use the New Application Property in VFP 5.0

For more information about Excel's Object Browser, please see the following article in the Microsoft Knowledge Base:

Q142128 XL: How to Find Visual Basic for Application Help

Additional query words: kbdsd VFoxWin

Keywords : kbVFp500 kbVFp600 FxinteropOle
Version : WINDOWS:5.0,6.0
Platform : WINDOWS
Issue type :