Why full calendar doesn't appear in asp.net? - asp.net

Question

My problem when I use MySQL server, the calendar was appear but when I change the connection to SQL server the calendar doesn't appear. I have no idea how to solve this problem. Is that anything that I have to change the code to make the calendar appear?
HTML:
<script type="text/javascript">
function Confirm() {
var confirm_value = document.createElement("INPUT");
confirm_value.type = "hidden";
confirm_value.name = "confirm_value";
if (confirm("Do you want to proceed ?")) {
confirm_value.value = "Yes";
} else {
confirm_value.value = "No";
}
document.forms[0].appendChild(confirm_value);
}
</script>
<script type="text/javascript">
function ConfirmEvent() {
var confirm_value_event = document.createElement("INPUT");
confirm_value_event.type = "hidden";
confirm_value_event.name = "confirm_value_event";
if (confirm("Do you want to proceed ?")) {
confirm_value_event.value = "Yes";
} else {
confirm_value_event.value = "No";
}
document.forms[0].appendChild(confirm_value_event);
}
</script>
<style type="text/css">
.style1 {
font-weight: bold;
width: 120px;
}
.style2 {
color: Blue;
font-weight: bold;
text-decoration: underline;
height: 25px;
}
.style5 {
color: Blue;
font-weight: bold;
text-decoration: underline;
}
.style6 {
width: 96px;
}
.style7 {
width: 150px;
}
</style>
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"></asp:ToolkitScriptManager>
<div id='calendar'>
</div>
VB.NET:
Public Class _Default
Inherits System.Web.UI.Page
Public eventstring As String
"server=xxx.xxx.x.x\SQLEXPRESS;database=attendance;uid=ab;pwd=abcde;"
Dim Conn As SqlConnection
Dim da As SqlDataAdapter
Dim cmd As SqlCommand
Dim rdmysql As SqlDataReader
Dim strsql As String
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim lbl As Label = Master.FindControl("lblHeader")
lbl.Text = "IT Attendance"
Dim startdate As String = Format(Now, "yyyy-MM-dd")
If txtStartDate.Value = "" Then txtStartDate.Value = startdate
If txtEndDate.Value = "" Then txtEndDate.Value = startdate
If txtStartEvent.Value = "" Then txtStartEvent.Value = startdate
If txtEndEvent.Value = "" Then txtEndEvent.Value = startdate
Conn = New SqlConnection
Conn.ConnectionString = ConnStr
Conn.Open()
eventstring = ""
strsql = "SELECT * FROM record;"
cmd = New SqlCommand
cmd.Connection = Conn
cmd.CommandText = strsql
rdmysql = cmd.ExecuteReader
Do While rdmysql.Read = True
eventstring = eventstring & "{title: '" & rdmysql.GetString(1) & " - " & rdmysql.GetString(3) & "', start: '" & rdmysql.GetString(2) & "', color: 'yellow', borderColor: 'black', textColor: 'black'},"
Loop
cmd.Dispose()
rdmysql.Close()
strsql = "SELECT * FROM event;"
cmd = New SqlCommand
cmd.Connection = Conn
cmd.CommandText = strsql
rdmysql = cmd.ExecuteReader
Do While rdmysql.Read = True
eventstring = eventstring & "{title: '" & rdmysql.GetString(1) & "', start: '" & rdmysql.GetString(2) & "', color: 'skyblue', textColor: 'black', borderColor: 'black'},"
Loop
cmd.Dispose()
rdmysql.Close()
eventstring = Mid(eventstring, 1, Len(eventstring) - 1)
Anyone can help me to solve this problem?