How do I compare the value of string array?

Question

I have declared a string array and I want to compare with name given by user,

string[] MasterList = new string[] {
  "Askay", "Puram", "Raman", "Srinivasa",
  "Gopal", "Rajesh", "Anju", "Nagara",
};

string YourName;
Console.WriteLine("Enter your name: ");
YourName = Console.ReadLine();

for(i=0; i<5; i++)
{
    a = String.Compare(MasterList[i], YourName);
    Console.WriteLine("Your name is not among the list")
}

The resulting output is not what I am expecting, any ideas how I can go about it?

Why use `i<5` when you have more than 5 indices in your array? Why not `MasterList.Length`? — Drew Kennedy, Jul 06 '17 at 14:24
Your code doesn't compile and you havent told what you expect. But simple: `if(!MasterList.Contains(YourName)){...}` instead of the for-loop. — Tim Schmelter, Jul 06 '17 at 14:25

Salah Akbari · Answer 1 · 2017-07-06T14:37:45.840

2

Why not use the Contains method?

Add the following line to your using directives first:

using System.Linq;

And then, remove the for loop and use the following line instead:

if (!MasterList.Contains(YourName, StringComparer.OrdinalIgnoreCase))
{
    Console.WriteLine("Your name is not among the list")
}

edited Jul 06 '17 at 14:37

answered Jul 06 '17 at 14:25

Salah Akbari

39,330
10
79
109

I think using `Contains` here is not safe, even it `Contains`, still may not be the name, should be fully matched – LONG Jul 06 '17 at 14:28

score 2 · Answer 2 · answered Jul 06 '17 at 14:26

Why not Contains?

  string[] MasterList = new string[] {
    "Askay", "Puram", "Raman", "Srinivasa",
    "Gopal", "Rajesh", "Anju", "Nagara",
  };

  Console.WriteLine("Enter your name: ");
  string YourName = Console.ReadLine();

  // StringComparer.OrdinalIgnoreCase if you want to ignore case
  // MasterList.Contains(YourName) if you want case sensitive 
  if (!MasterList.Contains(YourName, StringComparer.OrdinalIgnoreCase))
    Console.WriteLine("Your name is not among the list")

Peter Meadley · Accepted Answer · 2017-07-06T14:30:33.903

-1

bool found = false;
foreach (string s in MasterList)
{
    if(s == YourName)
    found = true;
}
if(found)
    Console.WriteLine("Your name is among the list");
else
    Console.WriteLine("Your name is not among the list");

edited Jul 06 '17 at 14:30

answered Jul 06 '17 at 14:27

Peter Meadley

509
2
16

1

Can people who are downvoting please give some comments to @Peter who is a relatively new user :) – garfbradaz Jul 06 '17 at 14:28
1

@garfbradaz if Peter cannot work out what is wrong with his answer there is always [How to write a good answer](https://stackoverflow.com/help/how-to-answer) – Jamiec Jul 06 '17 at 14:29
Thats what I mean @Jamiec - that is helpful, giving a link for guidance (I was trying to find it myself to post) - kudo! :) – garfbradaz Jul 06 '17 at 14:30
1

Comparing strings with `==` operators can yield unpredictable results (I did not downvote). You're referencing to see if it's the _exact same object_ (which strings often are not, regardless of contents). – gravity Jul 06 '17 at 14:30
1

@gravity see https://stackoverflow.com/questions/1659097/why-would-you-use-string-equals-over – Peter Meadley Jul 06 '17 at 14:31
@gravity Strings work differently in C# than they do in Java. `==` is safe. – Drew Kennedy Jul 06 '17 at 14:32
1

Thanks man...it worked just as i wanted it! thanks @Peter Meadley – Frederick Ottache Jul 06 '17 at 14:34
1

At very least break out of the loop when youve found the item. – Jamiec Jul 06 '17 at 14:35

How do I compare the value of string array?

3 Answers3