Call this member function to initialize data in a dialog box, or to retrieve and validate dialog data. BOOL UpdateData( BOOL bSaveAndValidate = TRUE );
查msdn,主要是将控件和数据关联CWnd::UpdateData BOOL UpdateData( BOOL bSaveAndValidate = TRUE );Return ValueNonzero if the operation is successful; otherwise 0. If bSaveAndValidate is TRUE, then a return value of nonzero means that the data is successfully validated.ParametersbSaveAndValidateFlag that indicates whether dialog box is being initialized (FALSE) or data is being retrieved (TRUE).ResCall this member function to initialize data in a dialog box, or to retrieve and validate dialog data.The framework automatically calls UpdateData with bSaveAndValidate set to FALSE when a modal dialog box is created in the default implementation of CDialog::OnInitDialog. The call occurs before the dialog box is visible. The default implementation of CDialog::OnOK calls this member function with bSaveAndValidate set to TRUE to retrieve the data, and if successful, will close the dialog box. (If the Cancel button is clicked in the dialog box, the dialog box is closed without the data being retrieved.)
BOOL UpdateData(
BOOL bSaveAndValidate = TRUE
);
实现变量与对话框中控件的信息映射(双向)
TRUE //dialog box->data
False//data ->dialog box
BOOL UpdateData( BOOL bSaveAndValidate = TRUE );Return ValueNonzero if the operation is successful; otherwise 0. If bSaveAndValidate is TRUE, then a return value of nonzero means that the data is successfully validated.ParametersbSaveAndValidateFlag that indicates whether dialog box is being initialized (FALSE) or data is being retrieved (TRUE).ResCall this member function to initialize data in a dialog box, or to retrieve and validate dialog data.The framework automatically calls UpdateData with bSaveAndValidate set to FALSE when a modal dialog box is created in the default implementation of CDialog::OnInitDialog. The call occurs before the dialog box is visible. The default implementation of CDialog::OnOK calls this member function with bSaveAndValidate set to TRUE to retrieve the data, and if successful, will close the dialog box. (If the Cancel button is clicked in the dialog box, the dialog box is closed without the data being retrieved.)
你调用这个函数的时候,就会调用到DataExchange这个函数,以此来实现控件和继承类之间的数据交换.