Rating Properties:

·         AutoPostBack - True to cause a postback on rating item click.

·         CurrentRating - Initial rating value

·         MaxRating - Maximum rating value

·         ReadOnly - Whether or not the rating can be changed

·         StarCssClass - CSS class for a visible star

·         WaitingStarCssClass - CSS class for a star in waiting mode

·         FilledStarCssClass - CSS class for star in filled mode

·         EmptyStarCssClass - CSS class for a star in empty mode

·         RatingAlign - Alignment of the stars (Vertical or Horizontal)

·         RatingDirection - Orientation of the stars.

·         OnChanged - ClientCallBack event to fire when the rating is changed

Code:

Default.aspx

 <%-- ScriptManager control manages client script for AJAX enabled ASP.NET pages.This enables partial-page rendering and Web-service calls.You have to used this if you want to use ajax control toolkit--%>
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
  
<cc1:Rating ID="Rating1" runat="server" MaxRating="5" CurrentRating="2" CssClass="rstar" StarCssClass="ritem" WaitingStarCssClass="svd" FilledStarCssClass="fld" EmptyStarCssClass="empt"  AutoPostBack="True" OnChanged="Rating1_Changed">
</cc1:Rating>
  
<asp:Label ID="Label2" runat="server" Text="Selected value:"></asp:Label>
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>

Here CurrentRating="2" so current star rating will be 2. StarCssClass="ratingItem" ratingItem is defined inStyleSheet.css. WaitingStarCssClass="Saved" saved isdefined inStyleSheet.css. FilledStarCssClass="Filled" filled is defined inStyleSheet.css .

Default.aspx.cs

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
 
public partial class _Default : System.Web.UI.Page
{
 
 
     const int rt_min = 1;
     const int rt_max = 5;
 
     protected void Page_Load(object sender, EventArgs e)
    {
        if( !IsPostBack )
        {
            Rating(Rating1.CurrentRating);
            
        }
    }
    
     protected void Rating1_Changed(object sender, AjaxControlToolkit.RatingEventArgs e)
    {
        Rating(int.Parse(e.Value));
    }
 
     public void Rating(int value) {
        Label1.Text = "Selected value  " + evalRating(value, Rating1.MaxRating, rt_min, rt_max);
    }
 
     public static string evalRating(int value, int maxvalue, int minrange, int maxrange)
    {
        int stepDelta = (minrange==0) ? 1 : 0;
        double delta = (double)(maxrange - minrange) / (maxvalue - 1);
        double result = delta * value - delta * stepDelta;
        return formatRes(result);
    }
 
     public static string formatRes(double value)
    {
        return String.Format("{0:g}", value);
    }
 
}

StyleSheet.css

We apply these style sheet in default.aspx page by using link tag

.rstar
{
       white-space:nowrap;
       margin:1em;
       height:14px;
}
.rstar .ritem {
     font-size: 0pt;
     width: 13px;
     height: 12px;
     margin: 0px;
     padding: 0px;
     display: block;
     background-repeat: no-repeat;
       cursor:pointer;
}
.rstar .fld {
     background-image: url(images/ratingStarFilled.png);
}
.rstar .empt {
     background-image: url(images/ratingStarEmpty.png);
}
.rstar .svd {
     background-image: url(images/ratingStarSaved.png);
}

Run the project

When you select the star then rating value will show