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+---
+title: Making Non-Special Days Unselectable in RadCalendar
+description: Learn how to make all non-special days unselectable in RadCalendar for ASP.NET AJAX.
+type: how-to
+page_title: How to Make Non-Special Days Unselectable in RadCalendar | RadCalendar for ASP.NET AJAX
+slug: calendar-making-non-special-days-unselectable
+tags: radcalendar, asp.net ajax, unselectable days, special days
+res_type: kb
+---
+# Environment
+| Product | Version |
+|---------|---------|
+| RadCalendar for ASP.NET AJAX | all |
+
+## Description
+I want to make all non-special days unselectable in my RadCalendar for ASP.NET AJAX. Currently, I am able to iterate through a list of dates and create blue special days that are selectable. However, I need to figure out how to make every day that is NOT special unselectable.
+
+## Solution
+To make all non-special days unselectable in RadCalendar, you can apply the solution from the [Disabling calendar days article](https://docs.telerik.com/devtools/aspnet-ajax/knowledge-base/datepicker-disabling-calendar-days). This solution involves replacing the default cell content with a span element and modifying the appearance of the disabled days. Here's how you can apply it to your scenario:
+
+1. Add the following JavaScript code to your ASPX page:
+
+```javascript
+<script type="text/javascript">
+    // necessary to disable non-special days on client-side navigation
+    function OnDayRender(calendarInstance, args) {
+        // convert the date-triplet to a javascript date
+        var jsDate = new Date(args.get_date()[0], args.get_date()[1] - 1, args.get_date()[2]);
+
+        // Check if the day is special
+        var specialDates = [new Date(2024, 4, 14), new Date(2024, 4, 20), new Date(2024, 5, 5)];
+        var isSpecial = specialDates.some(function (date) {
+            return date.getTime() === jsDate.getTime();
+        });
+
+        if (!isSpecial) {
+            var otherMonthCssClass = "rcOutOfRange";
+            args.get_cell().className = otherMonthCssClass;
+            // replace the default cell content (anchor tag) with a span element 
+            // that contains the processed calendar day number -- necessary for the calendar skinning mechanism 
+            args.get_cell().innerHTML = "<span>" + args.get_date()[2] + "</span>";
+            // disable selection and hover effect for the cell
+            args.get_cell().DayId = "";
+        }
+    }
+</script>
+```
+
+2. Modify your RadCalendar declaration in the ASPX page to include the `OnDayRender` client event handler:
+
+```html
+<telerik:RadCalendar ID="RadCalendar1" runat="server" AutoPostBack="true" EnableNavigation="True" NavigationCellPadding="10" EnableMultiSelect="false" RenderMode="lightweight"
+    OnDayRender="Calendar_OnDayRender">
+    <FastNavigationSettings EnableTodayButtonSelection="true"></FastNavigationSettings>
+    <ClientEvents OnDayRender="OnDayRender" />
+</telerik:RadCalendar>
+```
+
+3. Add the following VB.NET code to your ASPX.VB code-behind file:
+```C#
+    private List<DateTime> GetSpecialDates()
+    {
+        return new List<DateTime>
+        {
+            new DateTime(2024, 5, 14),
+            new DateTime(2024, 5, 20),
+            new DateTime(2024, 6, 5)
+        };
+    }
+
+    protected void Page_Load(object sender, EventArgs e)
+    {
+        // necessary not to repeat the special days on postback
+        if (!Page.IsPostBack)
+        {
+            RadCalendar1.SpecialDays.Clear();
+        }
+    }
+
+    // necessary to disable all non-special days on first page load
+    protected void Calendar_OnDayRender(object sender, Telerik.Web.UI.Calendar.DayRenderEventArgs e)
+    {
+        // Get the list of special dates
+        List<DateTime> specialDates = GetSpecialDates();
+
+        // Check if the current date is in the special dates list
+        if (specialDates.Contains(e.Day.Date))
+        {
+            // If it is a special date, make it selectable and style it
+            e.Day.IsSelectable = true;
+            e.Cell.BackColor = Color.Blue;
+        }
+        else
+        {
+            // If it is not a special date, make it non-selectable
+            e.Day.IsSelectable = false;
+            e.Cell.BackColor = Color.LightGray; // Optional: set a different color for non-selectable days
+
+            // Disable selection and hover effect for non-special days
+            string calendarSkin = RadCalendar1.Skin;
+            if (string.IsNullOrEmpty(calendarSkin))
+            {
+                calendarSkin = "Default";
+            }
+            string otherMonthCssClass = "rcOutOfRange";
+
+            // clear the default cell content (anchor tag) as we need to disable the hover effect for this cell
+            //e.Cell.Text = "";
+            e.Cell.CssClass = otherMonthCssClass; // set new CssClass for the disabled calendar day cells (e.g. look like other month days here)
+
+            // render a span element with the processed calendar day number instead of the removed anchor -- necessary for the calendar skinning mechanism 
+            Label label = new Label();
+            label.Text = e.Day.Date.Day.ToString();
+            //e.Cell.Controls.Add(label);
+
+            // disable the selection for the specific day
+            RadCalendarDay calendarDay = new RadCalendarDay();
+            calendarDay.Date = e.Day.Date;
+            calendarDay.IsSelectable = false;
+            calendarDay.ItemStyle.CssClass = otherMonthCssClass;
+            RadCalendar1.SpecialDays.Add(calendarDay);
+        }
+    }
+```
+```vb
+Private Function GetSpecialDates() As List(Of DateTime)
+    Return New List(Of DateTime) From {
+        New DateTime(2024, 5, 14),
+        New DateTime(2024, 5, 20),
+        New DateTime(2024, 6, 5)
+    }
+End Function
+
+Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
+    ' necessary not to repeat the special days on postback
+    If Not Page.IsPostBack Then
+        RadCalendar1.SpecialDays.Clear()
+    End If
+End Sub
+
+' necessary to disable all non-special days on first page load
+Protected Sub Calendar_OnDayRender(ByVal sender As Object, ByVal e As Telerik.Web.UI.Calendar.DayRenderEventArgs)
+    ' Get the list of special dates
+    Dim specialDates As List(Of DateTime) = GetSpecialDates()
+
+    ' Check if the current date is in the special dates list
+    If specialDates.Contains(e.Day.Date) Then
+        ' If it is a special date, make it selectable and style it
+        e.Day.IsSelectable = True
+        e.Cell.BackColor = Drawing.Color.Blue
+    Else
+        ' If it is not a special date, make it non-selectable
+        e.Day.IsSelectable = False
+        e.Cell.BackColor = Drawing.Color.LightGray ' Optional: set a different color for non-selectable days
+
+        ' Disable selection and hover effect for non-special days
+        Dim calendarSkin = RadCalendar1.Skin
+        If (calendarSkin = "") Then
+            calendarSkin = "Default"
+        End If
+        Dim otherMonthCssClass As String = "rcOutOfRange"
+
+        ' clear the default cell content (anchor tag) as we need to disable the hover effect for this cell
+        'e.Cell.Text = ""
+        e.Cell.CssClass = otherMonthCssClass ' set new CssClass for the disabled calendar day cells (e.g. look like other month days here)
+
+        ' render a span element with the processed calendar day number instead of the removed anchor -- necessary for the calendar skinning mechanism 
+        Dim label As Label = New Label
+        label.Text = e.Day.Date.Day.ToString
+        '  e.Cell.Controls.Add(label)
+
+        ' disable the selection for the specific day
+        Dim calendarDay As RadCalendarDay = New RadCalendarDay
+        calendarDay.Date = e.Day.Date
+        calendarDay.IsSelectable = False
+        calendarDay.ItemStyle.CssClass = otherMonthCssClass
+        RadCalendar1.SpecialDays.Add(calendarDay)
+    End If
+End Sub
+```
+
+This code will disable all non-special days and style them accordingly in your RadCalendar.
+
+