I have a function that takes "params string[] requested" as input and is supposed to use readline to get input from the user and see if any match and if anything matches then return what matches
static string inputCheck(params string[] requested){
string? userInput = Console.ReadLine();
IEnumerable<string> selected = requested.Where(n => n == userInput);
if (selected != null) return selected; //Error is here
return "Nothing Please Try again";
}
The error I get is "Cannot implicitly convert type 'System.Collections.Generic.IEnumerable' to 'string' (csharp0029)"
I would prefer a solution that uses linq
CodePudding user response:
Your method returns string
but you return a kind of list inside of your method. Solution:
public static List<string> InputCheck(params string[] requested)
{
Console.Write("search: ");
var userInput = Console.ReadLine();
var filteredList = requested
.Where(n => n == userInput)
.ToList();
return filteredList;
}
..so you can call the method like this:
var yourArray = new[]
{
"lorem",
"ipsum",
"dolor",
"sit",
"amet",
"lorem",
"ipsum",
"dolor",
"sit",
"amet"
};
var results = YourClass.InputCheck(yourArray);
if(results.Any())
{
foreach (var result in results)
Console.WriteLine(result);
}
CodePudding user response:
You need
static string inputCheck(params string[] requested){
string? userInput = Console.ReadLine();
var selected = requested.Where(n => n == userInput).FirstOrDefault(); <<<<===
if (selected != null) return selected; //Error is here
return "Nothing Please Try again";
}
Why? Where
returns an enumerable of the matches (even if there is only one). FirstOrDefault
will return the first one from the list or null if not found
Or even
static string inputCheck(params string[] requested){
string? userInput = Console.ReadLine();
var selected = requested.FirstOrDefault(n => n == userInput);
if (selected != null) return selected; //Error is here
return "Nothing Please Try again";
}
given that FirstOrDefault
takes an optional predicate
another alternative was
static string inputCheck(params string[] requested){
string? userInput = Console.ReadLine();
var selected = requested.Where(n => n == userInput);
if (selected.Any()) return selected.First();
return "Nothing Please Try again";
}