Calculate Age based on ASP.Net TextBox value using SQL query in C# and VB.Net

Hi Bhavesh23,

Check this example. Now please take its reference and correct your code.

HTML

<asp:TextBox ID="txtDob" runat="server" />
<asp:Button Text="Calculate" runat="server" OnClick="OnCalculate" />
<hr />
<asp:TextBox ID="txtAge" runat="server" />

Namespaces

C#

using System.Configuration;
using System.Data.SqlClient;
using System.Globalization;

VB.Net

Imports System.Configuration
Imports System.Data.SqlClient
Imports System.Globalization

Code

C#

protected void OnCalculate(object sender, EventArgs e)
{
    DateTime birthDate = DateTime.ParseExact(txtDob.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);
    SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["constr"].ConnectionString);
    SqlCommand cmd = new SqlCommand(string.Format("SELECT DATEDIFF(YY,'{0}',GETDATE())", birthDate), con);
    con.Open();
    string year = Convert.ToString(cmd.ExecuteScalar());
    con.Close();
    txtAge.Text = year;
}

VB.Net

Protected Sub OnCalculate(ByVal sender As Object, ByVal e As EventArgs)
    Dim birthDate As DateTime = DateTime.ParseExact(txtDob.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture)
    Dim con As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("constr").ConnectionString)
    Dim cmd As SqlCommand = New SqlCommand(String.Format("SELECT DATEDIFF(YY,'{0}',GETDATE())", birthDate), con)
    con.Open()
    Dim year As String = Convert.ToString(cmd.ExecuteScalar())
    con.Close()
    txtAge.Text = year
End Sub

Screenshot

its done sir.

i have replace below line.

DateTime birthDate = DateTime.ParseExact(birthdate.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);

to this line.

String birthdate = txtBirthdate.Text;

the final code for me is as below.

//DateTime birthDate = DateTime.ParseExact(birthdate.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);
String birthdate = txtBirthdate.Text;
SqlConnection con = new SqlConnection(this.con);
SqlCommand cmd = new SqlCommand("Select DATEDIFF(YEAR,CONVERT(datetime,'" + birthdate + "',103),CONVERT(datetime,ISSUEDATE,103)) FROM TableName", con);
//SqlCommand cmd = new SqlCommand("Select DATEDIFF(YEAR,'" + birthdate.Text + "'SYSDATETIME()", con);
con.Open();
string year = Convert.ToString(cmd.ExecuteScalar());
con.Close();
TxtAge.Text = year;