Generic List LastIndexOf() Method
.Net framework generic list LastIndexOf(T) method search for the specified object and return the zero-based index of the last
occurrence within the entire List<T>. this LastIndexOf(T) method exists under System.Collections.Generic namespace. the LastIndexOf(T)
method has a required parameter named 'item'. this parameter type is 'T'. the 'T' indicate the object to locate in the List<T> and the value
can be null for reference types.
LastIndexOf(T) method return value data type is System.Int32. return value is the zero-based index of the last occurrence of 'item' within the entire List<T>, if the element found. the method return -1, if the 'item' not found in List<T>. if the list contains multiple elements of same name then it return the index of last occurrence.
the following asp.net c# example code demonstrate us how can we get the index of specified element's last occurrence from a generic list in an asp.net application.
LastIndexOf(T) method return value data type is System.Int32. return value is the zero-based index of the last occurrence of 'item' within the entire List<T>, if the element found. the method return -1, if the 'item' not found in List<T>. if the list contains multiple elements of same name then it return the index of last occurrence.
the following asp.net c# example code demonstrate us how can we get the index of specified element's last occurrence from a generic list in an asp.net application.
GenericListLastIndexOfMethod.aspx
<%@ Page Language="C#" AutoEventWireup="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void Button1_Click(object sender, System.EventArgs e)
{
List<string> colors = new List<string>() {"DarkSlateBlue","Green","White"};
colors.Add("Snow");
colors.Add("Green");
Label1.Text = "List Elements....<br />";
foreach (string color in colors)
{
Label1.Text += "<br />" + color;
}
Label1.Text += "<br /><br />LastIndexOf color 'Green': " + colors.LastIndexOf("Green");
Label1.Text += "<br /><br />LastIndexOf color 'Snow': " + colors.LastIndexOf("Snow");
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Generic List LastIndexOf() - How to get the specific List element's last occurrence index</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h2 style="color:DarkSlateGray; font-style:italic;">
System.Collections.Generic.List LastIndexOf() Method
<br /> How to get the specific List element's last occurrence index
</h2>
<hr width="525" align="left" color="SlateBlue" />
<asp:Label
ID="Label1"
runat="server"
ForeColor="Magenta"
Font-Size="Large"
Font-Names="Courier New"
>
</asp:Label>
<br /><br />
<asp:Button
ID="Button1"
runat="server"
OnClick="Button1_Click"
Text="Test Generic List LastIndexOf() Method"
Height="45"
Font-Bold="true"
ForeColor="DodgerBlue"
/>
</div>
</form>
</body>
</html>
