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c# - How to convert a string to a list

Convert a String into a List
The String represents text as a sequence of UTF-16 code units. The String is a sequential collection of characters that is used to represent text. The String is a sequential collection of System.Char objects.

The following .net c# tutorial code demonstrates how we can convert a String instance into a List object. So, in this .net c# tutorial code we will split a String instance into a String Array then we will convert the String Array into a List object. Here we will split a String by a comma delimiter.

The String Split(Char[], StringSplitOptions) method splits a String into substrings based on specified delimiting characters and String split options. In this example .net c# code, we removed the empty entries using the String split options StringSplitOptions.RemoveEmptyEntries. So, using the Split(Char[], StringSplitOptions) method we can split a String into a String Array by a comma delimiter.

The String Split(char[]? separator, StringSplitOptions options) method returns an Array whose elements contain the substrings in this String that are delimited by one or more characters in the separator. So, we get a String Array from the source String instance by splitting it by a comma separator. Now, we have to convert the String Array into a List object.

The List class represents a strongly typed list of objects that can be accessed by index. The Enumerable ToList() method creates a List<T> from an IEnumerable<T>. So, using this Enumerable ToList() method we can convert a String Array object into a List object.

Finally, we split a String instance into a String Array by splitting it using a comma separator. Then we convert the String Array instance into a List object using the Enumerable ToList() method. This is the way we have applied in this .net c# tutorial to convert a String instance into a List object.
string-to-generic-list.aspx

<%@ Page Language="C#" AutoEventWireup="true"%>

<!DOCTYPE html>    
<script runat="server">  
    protected void Button1_Click(object sender, System.EventArgs e)
    {
        //this line create a string variable.
        string birds = "Crab Plover, Banded Stilt, Masked Lapwing, Kentish Plover";

        Label1.Text = "string of birds............<br />";
        Label1.Text += birds;

        //split string and create a generic list with string data type
        List<string> listOfBirds = birds.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries).ToList();

        Label1.Text += "<br /><br />list of birds............";
        foreach (string bird in listOfBirds)
        {
            Label1.Text += "<br />" + bird;
        }
    }    
</script>    

<html xmlns="http://www.w3.org/1999/xhtml">    
<head id="Head1" runat="server">    
    <title>c# example - string to generic list</title>    
</head>    
<body>    
    <form id="form1" runat="server">    
    <div>    
        <h2 style="color:MidnightBlue; font-style:italic;">    
            c# example - string to generic list
        </h2>    
        <hr width="550" align="left" color="Gainsboro" />    
        <asp:Label     
            ID="Label1"     
            runat="server"    
            Font-Size="Large"  
            >    
        </asp:Label>    
        <br /><br />  
        <asp:Button     
            ID="Button1"     
            runat="server"     
            Text="string to generic list"    
            OnClick="Button1_Click"  
            Height="40"    
            Font-Bold="true"    
            />    
    </div>    
    </form>    
</body>    
</html>

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