If you need to use information on more than one page, or if you need the information to persist across visits to the Web site, you must use another method for maintaining state. You can use application state, session state, or profile properties. View state information is serialized into XML and then encoded by using base encoding, which can generate large amounts of data. When the page is posted to the server, the contents of view state are sent as part of the page postback information.
If view state contains a large amount of information, it can affect performance of the page. Test the performance of your pages by using typical data for your application to determine whether the size of view state is causing performance problems.
For alternatives to using view state, see ASP. If you do not have to store control information for individual controls, you can disable view state for a control. If a control on a page is refreshed from the data store on each postback, you can turn view state off for that control in order to reduce the size of view state. For example, you might turn view state off for a control such as the GridView control. Even when you explicitly turn view state off, a hidden field is still sent to the browser to indicate that postback is occurring for the page.
Another consideration is that if the amount of data in a hidden field becomes large, some proxies and firewalls will prevent access to the page that contains them. Because the maximum allowed amount can vary with different firewall and proxy implementations, large hidden fields can cause intermittent problems. If the amount of data that is stored in the ViewState property exceeds the value specified in the page's MaxPageStateFieldLength property, the page splits view state into multiple hidden fields.
This reduces the size of individual hidden fields below the size that firewalls reject. Some mobile devices do not allow hidden fields at all. Therefore, view state will not work for those devices. For more information and alternatives, see ASP. In addition to view state, ASP. NET supports control state. The page uses control state to persist control information that must be retained between postbacks, even if view state is disabled for the page or for a control.
Like view state, control state is stored in one or more hidden fields. You can access view state information by using the page's ViewState property, which exposes a dictionary object. You can use this dictionary to store custom values. A typical use is to store the value of custom properties that you define in the page. Because view state is sent as a hidden field, you can make changes to view state until the page's PreRenderComplete event.
After the page is rendered to the browser, changes to view state will not be saved. The information in the hidden view state field can be seen by users if they view the source of the Web page and can decode base encoded strings. This creates a potential security issue. For more information about security issues with view state, see Securing View State later in this topic.
To save a value to view state, create a new item that contains the value to save and add the item to the view state dictionary. The following example shows an ASP. NET Web page with code that saves a string and an integer value in view state. Custom type converters see the TypeConverter class for more information. View state is the accumulation of the values of a server control's properties.
These values are automatically placed in the server control's ViewState property, which is an instance of the StateBag class. This property's value is then persisted to a string object after the save state stage of the server control life cycle. For more information, see ASP. When you author a custom server control with a custom view state, the view state can be managed explicitly with the SaveViewState and LoadViewState methods.
For information on implementing a custom session-state provider, see Implementing a Session-State Store Provider. Given some username and password, then click submit, it resets the entire page for further entry. Now in this scenario, if we click on restore button, it actually not given anything, because view state will not hold any data after page refresh.
Now after given user name and password and click on View Enables Submit button, it will give require result. Click on View Enabled Re-store last stored data from view state is displayed as below. Basically, passing username and password have been stored as a view state in the page life.
So when restore has been clicked passing data hold in view state coming into the page as user name and password. One more critical functionality of view state is it can be enabled or disabled for the specific text box on the web page. NET view state is really a wonderful feature coming with a web application by default. It has verities advantages and disadvantages as well, but still the most popular features for the ASP.
Implementation of view state in any web application is very easy and there has no requirement of server-specific resources to use view state development. It only happens because of one server, all the controls of the Web Page is created and after the round trip the server destroys all the instances.
So to retain the values of the controls we use state management techniques. Now I am showing you an example of what the problem is when we don't use view state. Step 1 Open Visual Studio Step 3 Now click on Solution Explorer. Step 5 After adding the WebForm6. View All. Windows 11 is Here. Read what is new in Windows
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