Some Common Differences in C# Programming

Difference between Concatenation and placeholder Syntax

using System;
class UserInteractive
{
   public static void Main()
   {
      string name;
      Console.WriteLine("What’s Your Name? ");
      Console.Write ("Enter Your Name: ");
      name=Console.ReadLine();
      Console.WriteLine("Hello! "+name+” nice to meet you ”+name”.”); //Concatenation
      Console.WriteLine(“Hello! {0} nice to meet you {1}.”,name,name); //placeholder
      // placeholder are most preferable way.
   }
}

Difference between Parse and TryPare 

• If the no. is in string format you have two option parse and try parse.
  
  
• Parse method throw an exception, if it cannot parse the value.
  
  
• Whereas TryParse() return a bool indication whether it succeeded or failed.
  
  
• Use parse() if you are sure the value use valid other wise use try parse. 

using System;
//use of parse
class ParseTesting
{
   public static void Main()
   {
      string strNumber="100";
      int i=int.Parse(strNumber);
      Console.WriteLine(i);
   }
}

using System;
//use of try parse
class TryparseTesting
{
   public static void Main()
   {
      string strNumber="100TG";
      int Result;
      bool IsConversionSucessful= int.TryParse(strNumber, out Result);
      if(IsConversionSucessful)
      {
         Console.WriteLine(Result);
      }
      else
      {
         Console.WriteLine("Please Enter a valid number");
      }
   }
}

Difference between | and || or & and && 

• If we use | or & it always check both the condition of statements whether it satisfies it or not it consume too much compiling time.
  
  
• Other hand if we use || or && if left hand condition of statements satisfy them they don’t go to the right hand side it saves the compiling time.