In this article, you will learn what is 'as' Keyword in c#
In many cases, we need to convert an Object(Type) into another Object(Type) and sometimes you may get InvalidCastException. So, to overcome such types of exceptions C# provides as operator keyword.
This operator returns the object when they are compatible with the given type and returns null if the conversion is not possible instead of throwing an exception.
'as' keyword checks the compatibility of one object type with another object type. In the case of compatibility, it will return the value of the new object type otherwise, null will be returned.
Syntax of 'as' keyword
Expression as dataType;using System;
using System.Text;
using System.Collections.Generic;
class usingcsharp{
public static void Main() {
// taking a string variable
string str1 = "abc";
// taking an Object type variable
// assigning var1 to it
object obj1 = str1;
// now try it to cast to a string
string str2 = obj1 as string;
if(str2 != null)
{
Console.WriteLine("Success");
}
// now try to cast it to List
List<string> mylist = obj1 as List<string>;
// checking Successfully cast or not
if(mylist != null)
{
Console.WriteLine("Success");
}
else
{
Console.WriteLine("Not Successfull");
}
}
} as Keyword in c#- In many cases, we need to convert an Object(Type) into another Object(Type) and sometimes you may get InvalidCastException. So, to overcome such types of exceptions C# provides as operator keyword. This operator returns the object when they are compatible with the given type and returns null if the conversion is not possible instead of throwing an exception. 'as' keyword checks the compatibility of one object type with another object type. In the case of compatibility, it will return the value of the new object type otherwise, null will be returned.
C# is a programming language developed by Microsoft that runs on the .NET Framework. C# is used to develop web, desktop, mobile, games and much more application.
C# is a object-oriented programming language developed by Microsoft within its .NET Framework. Led by Anders Hejlsberg, your basic C# programming
and will also take you through various advanced concepts related to C# programming language.
C# such as control statements, objects and classes, inheritance, constructor, destructor, this, static, sealed, polymorphism, abstraction, abstract class, interface, File IO, Collections, namespace, encapsulation, properties, indexer, arrays, strings, regex, exception handling, multithreading etc.
For example...
using System;
namespace MinifyCode
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello Minify Code");
}
}
}
Output: Hello Minify Code
In this article you will learn, what is server side controls. We will discuss each of these objects in due time. In this tutorial we will explore the Server object, the Request object, and the Response object.
Session
Application
Cache
Request
Response
Server
User
Trace
Server Object
The Server object in Asp.NET is an instance of the System.Web.HttpServerUtility class. The HttpServerUtility class provides numerous properties and methods to perform many type of jobs.
Methods and Properties of the Server object
The methods and properties of the HttpServerUtility class are exposed through the intrinsic Server object provided by ASP.NET.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Optimization;
using System.Web.Routing;
using System.Web.Security;
using System.Web.SessionState;
using System.Data.Entity;
namespace minifycode
{
public class Global : HttpApplication
{
void Application_Start(object sender, EventArgs e)
{
// Code that runs on application startup
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
// Initialize the product database.
Database.SetInitializer(new ProductDatabaseInitializer());
// Create custom role and user.
RoleActions roleActions = new RoleActions();
roleActions.AddUserAndRole();
// Add Routes.
RegisterCustomRoutes(RouteTable.Routes);
}
void RegisterCustomRoutes(RouteCollection routes)
{
routes.MapPageRoute(
"ProductsCategoryRoute",
"Category/{categoryName}",
"~/ProductList.aspx"
);
routes.MapPageRoute(
"ProductNameRoute",
"Product/{productName}",
"~/ProductDetails.aspx"
);
}
}
}