C# 无法将“字符串”转换为“System.Collections.Generic.IEnumerable”<string></string>

Question

I'm new with C# how can I fix the issue? The error is showing at the last line(query). Any help is appreciated!

using System;
using System.Collections.Generic;
using System.IO;

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

            var hobbies = new List<string>() { };
            Console.WriteLine("Please enter your name");
            string myName = Console.ReadLine();
            Console.WriteLine("Tell me something about you");
            string myAbout = Console.ReadLine();
            Console.WriteLine("What kind of hobbies do you have?");
            string myHobbies = Console.ReadLine();
            hobbies.Add(myHobbies);
            var query = myName + '\n' + myAbout + '\n' + myHobbies;
            File.AppendAllLines("C:\\test.txt", query);

        }
    }
}

Answer 1

As states in the docs for File.AppendAllLines , the method signature is

public static void AppendAllLines (string path, 
System.Collections.Generic.IEnumerable<string> contents);

ie the second argument is expected to be an IEnumerable<String> and you are passing query , which is a String . You probably want AppendAllText , which receives a String in the second argument.

Answer 2

The method expects a collection of strings as second parameter, but you provide only a string. You can use File.AppendAllText instead which works with a single string.

File.AppendAllText("C:\\test.txt", query);

Answer 3

You'll really get that error since your trying to combine a List into a string. Just iterate first whats inside of your List in a string that will hold its values before proceeding.

Just like below,

        List<string> hobbies = new List<string>();
        string hobbies_ = "";
       


        var hobbies = new List<string>() { };
        Console.WriteLine("Please enter your name");
        string myName = Console.ReadLine();
        Console.WriteLine("Tell me something about you");
        string myAbout = Console.ReadLine();
        Console.WriteLine("What kind of hobbies do you have?");
        string myHobbies = Console.ReadLine();
        hobbies.Add(myHobbies);
       

        foreach (var hobby in hobbies)
        {
            hobbies_ += hobbies + "\n";
        }

        var query = myName + '\n' + myAbout + '\n' + hobbies_;
        File.AppendAllLines("C:\\test.txt", query);