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QuestionXamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Luis M. Rojas22-Jul-22 7:18
Luis M. Rojas22-Jul-22 7:18 
AnswerRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Richard MacCutchan22-Jul-22 21:23
mveRichard MacCutchan22-Jul-22 21:23 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Luis M. Rojas23-Jul-22 3:34
Luis M. Rojas23-Jul-22 3:34 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Richard MacCutchan23-Jul-22 8:14
mveRichard MacCutchan23-Jul-22 8:14 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Luis M. Rojas23-Jul-22 11:59
Luis M. Rojas23-Jul-22 11:59 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Richard MacCutchan23-Jul-22 20:50
mveRichard MacCutchan23-Jul-22 20:50 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Luis M. Rojas25-Jul-22 3:21
Luis M. Rojas25-Jul-22 3:21 
GeneralRe: Xamarin using C#: System.NullReferenceException: 'Object reference not set to an instance of an object.' Pin
Richard Deeming25-Jul-22 4:37
mveRichard Deeming25-Jul-22 4:37 
NB: The as operator can and will return null if the object you're trying to cast cannot be converted to the target type.
Type-testing operators and cast expression - C# reference | Microsoft Docs[^]

You use as when you're not sure whether the object can be converted to the specified type; in which case, you should always check for null before using the variable. Using T y = x as T; without then checking for y == null is always a mistake.

When you're certain that the object will be of the desired type, you use a cast expression instead: T y = (T)x; In this case, there is no need to check for null, since the runtime would throw an exception if the conversion cannot be performed.

However, in this case, it would be far better to simply use the WebRequest.CreateHttp method, which has been available since .NET 4.5, and already returns the correct type:
WebRequest.CreateHttp Method (System.Net) | Microsoft Docs[^]



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QuestionIs is realistic to make money from a small mobile/tablet app? Pin
Patrick Skelton20-Mar-22 0:54
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Richard MacCutchan20-Mar-22 2:17
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QuestionHow to get started - app android and ios Pin
David Mikkelsen 20212-Mar-22 8:06
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20-Apr-22 22:46
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kevin james Jun202218-Aug-22 6:48
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GeneralRe: Why to Choose Mobile App Company in India for best out put? Pin
Richard Deeming8-Aug-22 22:06
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