如何使用C＃在LINQ中使用。

Question

I am trying to find a substring of states in a file. I open the file and load each line a string at a time. I would then like to check if each string contains one of the states in my substring. It is not working as intended as it keeps returning "Could not find substring" even though I know that the states are in the string. What am I doing wrong?

EDIT: I realise now what the error, this line was completely wrong:

if (lines.Any(stringToCheck.Contains))

It should be like this:

if (stringToCheck.Any(s.Contains))

Thanks for the help guys.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace ConsoleApplication2
{
    class Program
    {
       static void Main (string[] args)
    {

        string[] stringToCheck = {"Alabama","Alaska","Arizona","Arkansas","California","Colorado"}; 

        string[] lines = File.ReadAllLines(@"C:\C# Project\sampledata.dat");
        foreach (string s in lines)
        {
            if (lines.Any(stringToCheck.Contains))
            {
                Console.WriteLine("Found substring");
                Console.WriteLine(s);
                Console.ReadLine();
            }
            else
            Console.WriteLine("Could not find substring");
            Console.WriteLine(s);
            Console.ReadLine() ;
        }


    }
}

}

Answer 1

You could use Any over the list of states to check if there is any string for each state which contains on the line. For sample:

    if (stringToCheck.Any(x = > s.Contains(x))
    {
      // ...
    }

Answer 2

you could do something like this:

if(stringToCheck.Any(e => s.Contains(e)){
   //
}

Answer 3

You could do something like this:

string[] stringToCheck = { "Alabama", "Alaska", "Arizona", "Arkansas", "California", "Colorado" };

//Some test lines
string[] lines = { "sadnaskjd Alabama", "sadasd Arizona", "asdasdaer" };

//A bool telling me if I found anything, 
//you could skip the bool and just use else in the foreach :)
bool contains = false;


foreach ( var check in stringToCheck )
{
    if ( lines.Any( l => l.Contains( check ) ) )
    {
        Console.WriteLine( "Found substring" );
        Console.WriteLine( s );
        contains = true;
    }  
}

if ( contains == false )
{
    Console.WriteLine("Could not find substring");
    Console.ReadLine();
}

Answer 4

Try this idea:

if (line.Any(x=>CheckKeyWordsInLine(line, stringToCheck)){
     //The line contains one of the keywords
}else{
     //The line does not contain any of the keywords
}

Then define the CheckKeyWordsInLine function as:

bool CheckKeyWordsInLine(string line, string[] keywords){

 foreach(var key in keywords)
 {
   if(line.Contains(key))
   {
      return true;
   }
 }
 return false;
}