Common Dialogs

 What is a Common Dialog/Why use them?  Open Dialog  Save File As Dialog  Color Dialog  Font Dialog  Print Dialog

 A “Common” dialog is one that you will use often, and are familiar with  Save programmers work  Help users with consistent interface  Common dialogs are provided by Windows  Look/feel the same way for every application  Common properties  Easy to modify  Many available methods  Can override default behavior

 Used when you need to open a file  Drag/drop Open File control from the toolbox  Does not show on form, but in control tray  Display by calling on ShowDialog method: If ofdOpenFile.ShowDialog() = Windows.Forms.DialogResult.OK Then MessageBox(“The file is: “ & ofdOpenFile.FileName) Else MessageBox(“No file was selected.”) End If

 Function returns a predefined constant, based on the button pressed:  Abort  Cancel  Ingnore  No  None  OK  Retry  Yes

 Other properties on the control:  Filter property. You can set the initial filter.  Filter is a string with two parts  The text to show for the filter type  The file type  You can have multiple filters  Separate the filters with a pipe (“|”)  Example: ofdOpenFile.Filter = “Text files (*.txt)|*.txt|All files (*.*)|*.*”

 You can set the initial directory that is displayed with the InitialDirectory property ofd.OpenFile.InitialDirectory = “c:\users\marty\stonehill”  You can set the title of the Open Dialog with the Title property

 Used to save a file to a file name  Drag a Save File Dialog to the form  The InitialDirectory, Title, Filter properties are EXACTLY the same as the are for the Open Dialog  When you have the name of the file to save, you can open the file with normal file operations

 You can choose colors for your program at run time with the ColorDialog control  It is dragged to the form, modified, and opened exactly the same as the other common dialogs  You can set the initial color by setting the.Color property  If the user presses OK, the dialog returns the color selected in the.Color property cdColor.Color = Color.Blue If cdColor.ShowDialog() = Windows.Forms.DialogResult.OK Then MsgBox(“Color selected is: “ & cdColor.Color End If

 Same process as all other common controls  The results are returned in the.Font property  You can set the initial value with the.Font property  Then use that selected font by setting it for another control If fdFont.ShowDialog() = Windows.Forms.DialogResult.OK Then txtSomeTextBox.Font = fdFont.Font

 You can drag the Print Document Control to your form  Print by calling on the.Print method for the common control  This common dialog is a bit more complicated  When you tell the program to print, it calls on a PrintPage event to print the page  You must write the code in the print page event so that the page gets printed  See section 9.3 for more details