Introduction of control state in Asp.net
Control state in ASP.NET is a mechanism for storing and persisting the state of a control across postbacks. Control state is different from view state in that it is specific to a control, while view state is specific to a page.
Control state is stored in a hidden form field that is sent to the client and back to the server on each postback. The control state is serialized and deserialized by the ASP.NET framework.
Control state is typically used to store small amounts of critical data that are essential for the control to function across postbacks. For example, a pager control might store its current page number in control state.
Control state can be used with or without view state. However, it is important to note that control state is not affected by the view state setting. This means that control state will be persisted across postbacks even if view state is disabled.
Benefits of using control state
There are several benefits to using control state:
- Control state can be used to store small amounts of critical data that are essential for the control to function across postbacks.
- Control state is not affected by the view state setting, which means that it will be persisted across postbacks even if view state is disabled.
- Control state can be used to implement custom state management logic for controls.
Drawbacks of using control state
There are also a few drawbacks to using control state:
- Control state is stored in a hidden form field, which can increase the size of the page and reduce performance.
- Control state is not encrypted, so it is important to only store sensitive data in control state if absolutely necessary.
- Control state is specific to a control, which can make it difficult to reuse code.
When to use control state
Control state should be used sparingly and only for small amounts of critical data that are essential for the control to function across postbacks. Some examples of when to use control state include:
- Storing the current page number of a pager control.
- Storing the current selection state of a tree view control.
- Storing the current value of a text box control that is used to enter a search query.
How to use control state
To use control state, you must first register the control for control state. This can be done by calling the RegisterRequiresControlState() method on the page. Once the control is registered for control state, you can save and load control state using the SaveControlState() and LoadControlState() methods.
The following code shows how to save and load control state for a pager control:
C#
Latest updates on control state in ASP.NET
In ASP.NET Core, there have been a few changes to the way that control state is handled. For example, in ASP.NET Core, control state is stored in a separate hidden form field from view state. This can improve performance, as the control state does not need to be serialized and deserialized as often as view state.
In addition, in ASP.NET Core, there is a new ControlStateProvider interface that can be used to implement custom state management logic for controls. This can be useful for controls that need to store large amounts of data or that need to store data in a specific format.
Advantages of using control state in asp.net :
There are several advantages to using control state in ASP.NET:
- Performance: Control state is more efficient than view state, especially for large amounts of data. This is because control state is stored in memory on the server, while view state is serialized and sent to the client and back.
- Security: Control state is more secure than view state, because it is not exposed to the client. This makes it ideal for storing sensitive data, such as credit card numbers and passwords.
- Control: Control state gives you more control over how your data is stored and retrieved. For example, you can specify which properties of a control should be persisted in control state, and you can also implement your own custom serialization logic.
- Flexibility: Control state can be used to store any type of data, regardless of its complexity. This makes it a good choice for storing complex data structures, such as objects and graphs.
Here are some specific examples of how control state can be used in ASP.NET:
- To store the state of a custom control, such as a pagination control or a data grid.
- To store the state of a form, so that it can be restored if the user posts back the form with errors.
- To store the state of a wizard, so that the user can navigate back and forth between the steps of the wizard.
- To store the state of a game, so that the user can resume playing the game later.
Overall, control state is a powerful and flexible way to manage state in ASP.NET applications. It is particularly useful for applications that need to store large amounts of data, sensitive data, or complex data structures.
However, it is important to note that control state should not be used as a replacement for view state for all scenarios. View state is still the best way to manage state for simple forms and controls.
Disadvantage of using control state in asp.net :
The following are some of the disadvantages of using control state in ASP.NET:
- Control state is stored in a hidden form field, which can increase the size of the page and reduce performance.
- Control state is not encrypted, so it is important to only store sensitive data in control state if absolutely necessary.
- Control state is specific to a control, which can make it difficult to reuse code.
In addition to the above disadvantages, here are some other things to keep in mind when using control state:
- Control state is not persisted across server restarts.
- Control state can be tampered with by malicious users.
- Control state can make your code more complex and difficult to maintain.
When to avoid using control state
Control state should be avoided when:
- You need to store large amounts of data.
- You need to store sensitive data.
- You need to reuse the control code in different contexts.
In these cases, it is better to use a different state management technique, such as view state, session state, or application state.
How to use control state property:
To use the control state property in ASP.NET, you must first register the control for control state. This can be done by calling the RegisterRequiresControlState() method on the page. Once the control is registered for control state, you can save and load control state using the SaveControlState() and LoadControlState() methods.
The SaveControlState() and LoadControlState() methods serialize and deserialize the control state to and from a hidden form field. This means that the control state will be persisted across postbacks even if view state is disabled.
Important: Control state is not encrypted by default. If you need to store sensitive data in control state, you should encrypt the data before saving it.
When to use the control state property
The control state property should be used sparingly and only for small amounts of critical data that are essential for the control to function across postbacks. Some examples of when to use the control state property include:
- Storing the current page number of a pager control.
- Storing the current selection state of a tree view control.
- Storing the current value of a text box control that is used to enter a search query.
When to avoid using the control state property
The control state property should be avoided when:
- You need to store large amounts of data.
- You need to store sensitive data.
- You need to reuse the control code in different contexts.
In these cases, it is better to use a different state management technique, such as view state, session state, or application state.
Conclusion
Control state is a useful mechanism for storing and persisting the state of a control across postbacks. However, it is important to use control state sparingly and only for small amounts of critical data.