How to display a message box with yes or no in asp net webforms using vb.net?

Question

Before inserting the record to the table,the system will check first if the first name and last name of the person is already exists. If the person is existing, a message box will appear with yes or no button asking if the user want to continue inserting the record.I have tried the following code:

Imports ChurchMIS.Data
Imports System
Imports System.Collections.Generic
Imports System.Data
Imports System.Linq
Imports System.Text.RegularExpressions
Imports System.Web
Imports System.Web.Security
Imports System.Data.SqlClient
Namespace ChurchMIS.Rules

Partial Public Class IndividualBusinessRules
    Inherits ChurchMIS.Data.BusinessRules

    ''' <summary>
    ''' This method will execute in any view for an action
    ''' with a command name that matches "SQL".
    ''' </summary>
    <Rule("r107")>  _
    Public Sub r107Implementation( _
                ByVal individualId As Nullable(Of Integer),  _
                ByVal firstName As String,  _
                ByVal lastName As String,  _
                ByVal dateOfBirth As Nullable(Of DateTime),  _
                ByVal addressTypeId As Nullable(Of Integer),  _
                ByVal suburb As String,  _
                ByVal streetAddress As String,  _
                ByVal postCode As Nullable(Of Integer),  _
                ByVal contactInfoTypeId As Nullable(Of Integer),  _
                ByVal contactNo As String,  _
                ByVal fullName As String,  _
                ByVal individualTypeId As Nullable(Of Integer),  _
                ByVal state As String,  _
                ByVal dateOfBaptism As Nullable(Of DateTime),  _
                ByVal dateOfTransfer As Nullable(Of DateTime),  _
                ByVal email As String,  _
                ByVal faithStatus As Nullable(Of Integer),  _
                ByVal noOfVisits As Nullable(Of Integer),  _
                ByVal name As String,  _
                ByVal name_1 As String,  _
                ByVal name_2 As String)
        'This is the placeholder for method implementation.
        Dim con As SqlConnection = New SqlConnection("Data     Source=CNEPHILS;Initial Catalog=ChurchMIS;User ID=sa;Password=Cn$phil$")

        Dim theQuery As String = "SELECT * FROM Individual WHERE  FirstName=@FirstName AND LastName=@LastName"
        Dim cmd1 As SqlCommand = New SqlCommand(theQuery, con)
        cmd1.Parameters.AddWithValue("@FirstName", firstName)
        cmd1.Parameters.AddWithValue("@LastName", lastName)

        Using reader As SqlDataReader = cmd1.ExecuteReader()
            If reader.HasRows Then
                ' person already exists
                    Dim result As Integer=

                Dim result As Integer = MessageBox.Show("message",  "caption", MessageBoxButtons.YesNoCancel)
                If result = DialogResult.Cancel Then
                    MessageBox.Show("Cancel pressed")
                ElseIf result = DialogResult.No Then
                    MessageBox.Show("No pressed")
                ElseIf result = DialogResult.Yes Then
                    Dim cmd As SqlCommand = New SqlCommand("exec  spInsertIndividual @FirstName,@LastName,@DateOfBirth,@Suburb,@StreetAddress,@PostCode,@State,@AddressTypeId,@ContactInfoTypeId,@ContactNo,@IndividualTypeId,@Email,@FaithStatus,@DateOfBaptism,@DateOfTransfer", con)
                    cmd.ExecuteNonQuery()
                    MsgBox("Records Successfully Added!", MsgBoxStyle.Information)
                End If
            Else
                ' person does not exist, add them
                Dim cmd As SqlCommand = New SqlCommand("exec spInsertIndividual @FirstName,@LastName,@DateOfBirth,@Suburb,@StreetAddress,@PostCode,@State,@AddressTypeId,@ContactInfoTypeId,@ContactNo,@IndividualTypeId,@Email,@FaithStatus,@DateOfBaptism,@DateOfTransfer", con)
                cmd.ExecuteNonQuery()
                MsgBox("Records Successfully Added!", MsgBoxStyle.Information)
            End If
        End Using

        con.Close()

    End Sub
End Class
End Namespace

However,i raised an error "MessageBox is not declared.....protection level."

Hope someone could help. Thanks!

Answer 1

@roger. I think your are working in web application. try this, add this script in your .aspx page inside the head tag.

<script type="text/javascript">
        function SomeMethod() {
            try {
                var result = true;
                var obj = {};
                obj.Firstname = $('#<%=txtfirstname.ClientID %>').val();
                obj.Lastname = $('#<%=txtlastname.ClientID %>').val();
                $.ajax({
                    type: "POST",
                    data: JSON.stringify(obj),
                    url: "yourformname.aspx/yourmethodname",
                    contentType: "application/json; charset=utf-8",
                    dataType: "json",
                    async:false,
                    success: function (response) {
                        if (response.d.toString() == "true") {
                                if (confirm("first name and last name of the person is already exists?")) {
                                    result = true;
                                    // insert the user name
                                }
                                else {
                                    result = false;

                                }
                        }
                        else {

                        }
                    },
                    failure: function (response) {
                        alert(response.d);
                    }
                });
            }
            catch (e) {
                alert(e);
            }
            return result;
        }
    </script>

call the javascript function in your button click event. if your are using RequiredFieldValidator for validation use the Page_ClientValidate() other wise remove that Page_ClientValidate() function in the button onclick event.

<asp:Button ID="btnbutton" CssClass="Designclass" OnClientClick="if(Page_ClientValidate()) return SomeMethod();"
                                        runat="server" Text="Generate" />

create the following web method in your .aspx.vb page

 <System.Web.Services.WebMethod()>
Public Shared Function Checkuserexists(ByVal Firstname As String, ByVal Lastname As String) As String
    'write your code for checking firstname and last name
     If exists > 0 Then
        Return true
    Else
        Return False
    End If
End Function

By using Checkuserexists method check the firstname and last name is exists in the database. if the first name and last name exists its returns true and ask for conform message. if you click yes its insert the value into the database.