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Tsavedialog - displays a dialog for selecting a save file name

type TSaveDialog; Description The TSaveDialog is a visual component. It is used to allow a user to select the name of a file to save to. It can be defined by dragging the save dialog icon from the Dialogs tab in Delphi, or by defining a TSaveDialog variable. The TSaveDialog can be configured to suit your needs. When using it, you would proceed along the following steps: Creating the dialog object You define a TSaveDialog variable, and then assign a new TSaveDialog object to it: var saveDialog : TSaveDialog; begin saveDialog := TSaveDialog.Create(self); Note that the dialog must have an anchor - here we provide the current object - self - as the anchor. Setting options Before displaying the dialog, you are likely to configure it to your needs by setting the dialog properties. Here are the main properties: Title property Gives the caption to the dialog. FileName property Gives a default file name to save. (Otherwise, the file name field is blank). DefaultExt property Defines the extension that will be added to the user file name, if manually typed (rather than selected from the file list). If their are two or more save filter extension types, then this value is ignored. However, it must be provided in order for the drop down list extension values to be used. Strange! Filter property This allows only certain file types to be displayed and selectable. The filter text is displayed in a drop down below the file name field. The following example selects for text files only: saveDialog.Filter := 'Text files only|*.txt'; The drop down dialog shows the description before the | separator. After the separator, you define a mask that selects the files you want. saveDialog.Filter := 'Text files|*.txt|Word files|*.doc'; Above we have allowed text and Word files as two options in the drop down list. FilterIndex property Defines which (starting at 1) of the drop down filter choices will be displayed first. InitialDir property Sets the starting directory in the dialog. Displaying the dialog We now call a method of TSaveDialog: if saveDialog.Execute then ... Execute returns true if the user selected a file and hit OK. You can then save to the selected file: Finishing with the dialog The selected file obtained using the following property: FileName property This holds the full path plus file name of the selected file. Finally, we must free the dialog object: saveDialog.free; Notes It is your responsibility to detect whether the user has selected an existing file - you will want to ask the user if the file should be overriden. Related commands Append Open a text file to allow appending of text to the end AssignFile Assigns a file handle to a binary or text file PromptForFileName Shows a dialog allowing the user to select a file Reset Open a text file for reading, or binary file for read/write TOpenDialog Displays a file selection dialog Example code : var saveDialog : TSaveDialog; // Save dialog variable begin // Create the save dialog object - assign to our save dialog variable saveDialog := TSaveDialog.Create(self); // Give the dialog a title saveDialog.Title := 'Save your text or word file'; // Set up the starting directory to be the current one saveDialog.InitialDir := GetCurrentDir; // Allow only .txt and .doc file types to be saved saveDialog.Filter := 'Text file|*.txt|Word file|*.doc'; // Set the default extension saveDialog.DefaultExt := 'txt'; // Select text files as the starting filter type saveDialog.FilterIndex := 1; // Display the open file dialog if saveDialog.Execute then ShowMessage('File : '+saveDialog.FileName) else ShowMessage('Save file was cancelled'); // Free up the dialog saveDialog.Free; end; Show full unit code An save file dialog is displayed with two drop down filter choices: Delphi project files Delphi pascal files - this is displayed at the start The dialog is positioned to the current directory (which will be the Delphi project directory if running the code from within Delphi). If you select a file, such as 'Unit1.pas' then it is displayed in the ShowMessage dialog like this: File : C:Program FilesBorlandDelphi7ProjectsUnit1.pas