String Join() Method
The following asp.net c# example code demonstrate us how can we use .net framework's String Class Join() method
in an asp.net application. String.Join() method allow us to concatenate the elements of a specified array or the members
of a collection, using the specified separator between each element or member.
This member is overloaded, those are String.Join(String, IEnumerable<String>), Join<T>(String, IEnumerable<T>),
Join(String, Object[]), Join(String, String[]) and Join(String, String[], Int32, Int32). In this tutorial, we only discuss
about String.Join(String, String[]) overloaded method.
String.Join(String, String[]) method concatenate all the elements of a string array, using the specified separator between
each element. This method require to pass two parameters named 'separator' and 'value'. The 'separator' parameter value represent
a string to use as a separator and 'value' parameter represent an array that contains the elements to concatenate.
In this example, we concatenate a string array's elements by using a comma and a white space (, ) separator. Finally we get a System.String
object from a specified array elements where array items are separated by specified separator.
Join.aspx
<%@ Page Language="C#" %>
<!DOCTYPE html>
<script runat="server">
private string[] colorArray = { "Red", "Green", "Yellow", "HotPink", "SeaGreen" };
protected void page_Load(object sender, System.EventArgs e) {
if(!this.IsPostBack)
{
ListBox1.DataSource = colorArray;
ListBox1.DataBind();
}
}
protected void Button1_Click(object sender, System.EventArgs e) {
string testString = string.Join(", ", colorArray);
Label1.Text = "Joined successfully: " + testString;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>How to join an array of strings (elements) into a new string with specific separator</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h2 style="color:Green">asp.net string example: Join()</h2>
<asp:Label
ID="Label1"
runat="server"
Font-Size="Large"
ForeColor="Crimson"
Font-Bold="true"
Font-Italic="true"
>
</asp:Label>
<br /><br />
<asp:Label
ID="Label2"
runat="server"
ForeColor="DodgerBlue"
Font-Bold="true"
Text="ListBox populated by an array"
>
</asp:Label>
<br />
<asp:ListBox
ID="ListBox1"
runat="server"
BackColor="DodgerBlue"
ForeColor="Snow"
>
</asp:ListBox>
<br /><br />
<asp:Button
ID="Button1"
runat="server"
OnClick="Button1_Click"
Font-Bold="true"
Text="Join array elements and build String"
ForeColor="DodgerBlue"
/>
</div>
</form>
</body>
</html>
