STRING , STRINGBUILDER AND ITS FUNCTION IN C#

faq.txt

Q1) What is the difference between String and stringbuilder?
ans: string are immutable whereas Stringbuilder are mutable.

Q2) What is the function to trim only the leftside of the string?
ans: TrimStart function is use to trim the left side of the string and TrimEnd function is use to trim the right side of the string.


Q3)How to find whether a string is present in a string ?
ans: To check whether whether a string is present in the string or not , we will use the Contains function.
     string st="hello pepcoder";
     Console.WriteLine(st.Contains("hello"));  => true

Q4) What is the difference between append and appendformar in stringbuilder?
ans: Append function is used to append just a simple string eg. str.append("hello").
     AppendFormat function is used to append formatted string in a stringbuilder eg.str.append("hello {0}","pepcoder");

Mcq.txt

Q1) What will be the output of this code?

    string str="hello pepcoder";
    Console.WriteLine(str.Substring(0,8));
a) hello pe
b) hello pep
c) ello pe
d) ello pep

ans: b)

Q2) Output of this code?

      string str="hello pepcoder";
      Console.WriteLine(str.StartsWith("He"));
a) error
b) true
c) false
d) 0

ans: c)

Q3) What will be the output?

     string str="hello pepcoder";
     Console.WriteLine(str.Equals("Hello pepcoder",StringComparison.OrdinalIgnoreCase)); 

a) true
b) false
c) none
d) any of the above

ans: a)true

Q4) What is the output of this code?
      
    StringBuilder str= new StringBuilder ("hello pepcoder");
    str.Remove(2,3);  
    Console.WriteLine(str.ToString());
    
a) hel pepcoder
b) he pepcoder
c) hell pepcoder
d) None of the above

ans: b)