There are multiple ways to take a screen capture of your front panel programmatically.
If you have the Report Generation Toolkit you are easily able to take a screenshot of the LabVIEW Front Panel and have it automatically load the image to a new Microsoft Word Document. You can perform this using Easy Print Front Panel
.vi. Below is a snippet of printing the front panel using the Report Generation Toolkit.
You can also take a screenshot of a Front Panel Object or the Front Panel using Invoke Nodes. You can use the Get Image Invoke Nodes for either the Front Panel in relationship to the VI or a specific object. This method does use the Graphics Format functions to save the screenshot as a picture file.
For more information on saving and printing the Front Panel in LabVIEW, see the related links section.