How to convert List & lt; string & gt; to string and list to string

How to convert List <string> to string and list to string

Convert List, string.A List can be converted to a string. This is possible with the ToArray method on the List type. We can also convert a string into a List. Conversions
The StringBuilder typeHelps with certain conversions, which are done with loops. When using StringBuilder, we must be careful with a trailing delimiter.
First example.We use the string. Join method to combine a List of strings into one string. The output can be used as a CSV record. On new. NET Framework versions, ToArray is not required.

However:In previous versions, we had to call ToArray on a List before using Join. In older programs this is still required.

List

Based on: .NET 4C# program that converts Listusing System;using System.Collections.Generic;class Program{    static void Main()    {List<string> dogs = new List<string>();dogs.Add("Aigi"); // Add string 1dogs.Add("Spitz"); // 2dogs.Add("Mastiff"); // 3dogs.Add("Finnish Spitz"); // 4dogs.Add("Briard"); // 5string dogCsv = string.Join(",", dogs.ToArray());Console.WriteLine(dogCsv);    }}OutputAigi,Spitz,Mastiff,Finnish Spitz,Briard

Example 2.Here we use the StringBuilder class to convert a List to a single string. Note that you can convert a List of any object type into a string this way. StringBuilder

Final delimiter:The example has a final delimiter on the end. This is not present in code that uses string. Join. It can be inconvenient.

TrimEnd:Sometimes, it is good to remove the end delimiter with TrimEnd. Other times it is best left alone.

TrimEnd, TrimStart

C# program that uses List and StringBuilderusing System;using System.Collections.Generic;using System.Text;class Program{    static void Main()    {List<string> cats = new List<string>(); // Create new list of stringscats.Add("Devon Rex"); // Add string 1cats.Add("Manx"); // 2cats.Add("Munchkin"); // 3cats.Add("American Curl"); // 4cats.Add("German Rex"); // 5StringBuilder builder = new StringBuilder();foreach (string cat in cats) // Loop through all strings{    builder.Append(cat).Append("|"); // Append string to StringBuilder}string result = builder.ToString(); // Get string from StringBuilderConsole.WriteLine(result);    }}OutputDevon Rex|Manx|Munchkin|American Curl|German Rex|

Example 3.Here we convert a List of ints into a single string. The StringBuilder's Append method has es a variety of types. We can simply pass it the int.

And:Append () will handle the int on its own. It will convert it to a string and append it.

Performance:StringBuilder is fast for most programs. More speed cocould be acquired by using a char [] and then converting to a string.

Char Array

C# program that converts List typesusing System;using System.Collections.Generic;using System.Text;class Program{    static void Main()    {List<int> safePrimes = new List<int>(); // Create list of intssafePrimes.Add(5); // Element 1safePrimes.Add(7); // Element 2safePrimes.Add(11); // Element 3safePrimes.Add(23); // Element 4StringBuilder builder = new StringBuilder();foreach (int safePrime in safePrimes){    // Append each int to the StringBuilder overload.    builder.Append(safePrime).Append(" ");}string result = builder.ToString();Console.WriteLine(result);    }}Output5 7 11 23

Example 4.Finally, we get a List of strings from a string in CSV format. This requires the Split method. If you require per-item conversion, loop over the string array returned by Split.

C# program that converts string to Listusing System;using System.Collections.Generic;class Program{    static void Main()    {string csv = "one,two,three"; // The input stringstring[] parts = csv.Split(','); // Call Split methodList<string> list = new List<string>(parts); // Use List constructorforeach (string item in list){    Console.WriteLine(item);}    }}Outputonetwothree

A summary.We converted Lists and strings using the string. Join methods and the StringBuilder approach. The List is easily concatenated and stored in a database or file with these methods.