Callback_Handle / CBHNDL

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Callback_Handle / CBHNDL

 

Description

 

Meta function automatically created by thinBasic engine and valid only inside Callback Functions.

 

This meta function is valid only inside a Callback Function,

It returns the window handle of the caller.

 

Syntax

 

hWin = CBHNDL

alias

hWin = Callback_Handle

 

Returns

 

Number.

 

Remarks

 

When a user clicks on a button, types into a text box, or generally interacts with any  in a dialog, Windows sends a %WM_COMMAND message to the control callback function. If no control callback function is defined, the message is sent to the dialog callback function. In either type of callback, CBHNDL returns the window handle of the parent dialog. CBHNDL will also return the window handle for all other types of messages that flow through dialog callback functions. For example, %WM_PAINT, %WM_INITDIALOG, etc.

 

As it is possible to share a control callback function with multiple controls, it is also possible to share a dialog callback function with multiple dialogs. In such cases, CBHNDL can be used to make a clear distinction between each dialog.

 

Restrictions

 

This function is only valid inside a Callback Function.

 

See also

 

Examples