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PassThrough property

Project: Drop Files Components.

Unit: PJDropFiles.

Class: TPJCtrlDropFiles

Applies to: ~>5.0

property PassThrough: Boolean;


PassThrough causes drop files messages to be optionally passed through to the owning form.

When the property is false (default), and the control is enabled, any drop files messages intercepted by this control on behalf of the managed control are not forwarded to the form.

When PassThrough is true, and the control is enabled, then normal processing occurs when files are dropped. WM_DROPFILES messages are converted to custom PJ_DROPFILES message and forwarded to the form. Any TPJFormDropFiles component on the form can intercept PJ_DROPFILES messages and handle them like a standard WM_DROPFILES message.

When the drop files message is passed through, the drop point is converted into form coordinates and sent to the form as part of the PJ_DROPFILES message. In this way a TPJFormDropFiles component has its DropPoint property set to the correct value in terms of the form.