Calculate number of days between two dates in ASP.Net using C# and VB.Net

Hi akhter,

Please refer below sample.

HTML

<table>
    <tr>
        <td>Start Date :</td>
        <td>
            <asp:TextBox ID="txtStartDate" runat="server" />
        </td>
    </tr>
    <tr>
        <td>End Date</td>
        <td>
            <asp:TextBox ID="txtEnddate" runat="server" />
        </td>
    </tr>
    <tr>
        <td></td>
        <td>
            <asp:Button ID="btnCalculate" runat="server" Text="Calculate" OnClick="Calculate" />
        </td>
    </tr>
</table>
<asp:Label ID="lblDays" runat="server"></asp:Label>

Namespace

C#

using System.Globalization;

VB.Net

Imports System.Globalization

Code

C# 

protected void Calculate(object sender, EventArgs e)
{
    TimeSpan i = new TimeSpan(0, 0, 0);
    DateTime startDate = Convert.ToDateTime(this.txtStartDate.Text.Trim(), new CultureInfo("en-Gb"));
    DateTime endDate = Convert.ToDateTime(this.txtEnddate.Text.Trim(), new CultureInfo("en-Gb"));
    i += endDate.Subtract(startDate);
    int days = i.Days + 1;
    this.lblDays.Text = "Days Count is : " + days.ToString();
}

VB.Net

Protected Sub Calculate(ByVal sender As Object, ByVal e As EventArgs)
    Dim i As TimeSpan = New TimeSpan(0, 0, 0)
    Dim startDate As DateTime = Convert.ToDateTime(Me.txtStartDate.Text.Trim(), New CultureInfo("en-Gb"))
    Dim endDate As DateTime = Convert.ToDateTime(Me.txtEnddate.Text.Trim(), New CultureInfo("en-Gb"))
    i += endDate.Subtract(startDate)
    Dim days As Integer = i.Days + 1
    Me.lblDays.Text = "Days Count is : " & days.ToString()
End Sub

Screenshot