You currently cannot bind to some properties in Windows Forms. The most notable example is the ClientSize property, as binding to this property would cause unpredictable behavior at run time. You can usually work around these issues by saving and loading these settings programmatically. Application settings has no built-in facility for encrypting information automatically. You should never store security-related information, such as database passwords, in clear text.
If you want to store such sensitive information, you as the application developer are responsible for making sure it is secure. If you want to store connection strings, we recommend that you use Windows Integrated Security and not resort to hard-coding passwords into the URL.
When you define settings this way, Visual Studio automatically creates a custom managed wrapper class that associates each setting with a class property. Visual Studio also takes care of binding the setting to a property on a form or control so that the control's settings are restored automatically when its form is displayed, and saved automatically when the form is closed.
If you want more detailed control over your settings, you can define your own custom applications settings wrapper class. This is accomplished by deriving a class from ApplicationSettingsBase , adding a property that corresponds to each setting, and applying special attributes to these properties. For details about creating wrapper classes, see Application Settings Architecture. You can also use the Binding class to bind settings programmatically to properties on forms and controls.
Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Define a property on this wrapper class for each application setting you require, and apply that property with either the ApplicationScopedSettingAttribute or UserScopedSettingAttribute , depending on the scope of the setting.
For more information about settings scope, see Application Settings Overview. By now, your code should look like this:. Create an instance of this wrapper class in your application. It will commonly be a private member of the main form.
Now that you have defined your class, you need to bind it to a property; in this case, the BackColor property of your form. You can accomplish this in your form's Load event handler. If you provide a way to change settings at run time, you will need to save the user's current settings to disk when your form closes, or else these changes will be lost.
You have now successfully created a new application setting and bound it to the specified property. The default settings provider, LocalFileSettingsProvider , persists information to configuration files as plain text. This limits security to the file access security provided by the operating system for the current user. For more information on creating your own settings class in code, see How to: Create Application Settings. The location of the app. For a Windows Forms-based application copied onto the local computer, app.
LocalUserAppDataPath property. The storage location of these files is slightly different if a user has enabled roaming profiles, which enables a user to define different Windows and application settings when they are using other computers within a domain. In that case, both ClickOnce applications and non-ClickOnce applications will have their app.
For more information about how the Application Settings feature works with the new deployment technology, see ClickOnce and Application Settings. Application settings are designed to work in partial trust, a restricted environment that is the default for Windows Forms applications hosted over the Internet or an intranet.
No special permissions beyond partial trust are needed to use application settings with the default settings provider. When application settings are used in a ClickOnce application, the user. The size of the application's user.
For more information, see ClickOnce and Application Settings. In the Application Settings architecture, there is a loose coupling between the applications settings wrapper class, derived from ApplicationSettingsBase , and the associated settings provider or providers, derived from SettingsProvider.
This association is defined only by the SettingsProviderAttribute applied to the wrapper class or its individual properties. If a settings provider is not explicitly specified, the default provider, LocalFileSettingsProvider , is used. As a result, this architecture supports creating and using custom settings providers. For example, suppose that you want to develop and use SqlSettingsProvider , a provider that will store all settings data in a Microsoft SQL Server database. Your SettingsProvider -derived class would receive this information in its Initialize method as a parameter of type System.
You would then implement the GetPropertyValues method to retrieve your settings from the data store, and SetPropertyValues to save them. Your provider can use the SettingsPropertyCollection supplied to GetPropertyValues to determine the property's name, type, and scope, as well as any other settings attributes defined for that property. Your provider will need to implement one property and one method whose implementations may not be obvious.
The ApplicationName property is an abstract property of SettingsProvider ; you should program it to return the following:. Your derived class must also implement an Initialize method that takes no arguments and returns no value. This method is not defined by SettingsProvider. Finally, you implement IApplicationSettingsProvider on your provider to provide support for refreshing settings, reverting settings to their defaults, and upgrading settings from one application version to another.
Once you have implemented and compiled your provider, you need to instruct your settings class to use this provider instead of the default. You accomplish this through the SettingsProviderAttribute. If applied to an entire settings class, the provider is used for each setting that the class defines; if applied to individual settings, Application Settings architecture uses that provider for those settings only, and uses LocalFileSettingsProvider for the rest.
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