Create Wallet system using C# and VB.Net in ASP.Net

Hi donalduko,

Refer below example.

Database

CREATE TABLE tblUser
(
	Id INT IDENTITY PRIMARY KEY,
	UserId VARCHAR(100) NOT NULL,
	Password VARCHAR(100) NOT NULL
)

CREATE TABLE tblWallet
(
	Id INT IDENTITY PRIMARY KEY,
	UserId VARCHAR(100) NOT NULL,
	Amount DECIMAL(18,2) NOT NULL
)

HTML

<table>
    <tr>
        <td>UserId</td>
        <td><asp:TextBox runat="server" ID="txtUserId" /></td>
    </tr>
    <tr>
        <td>Passowrd</td>
        <td><asp:TextBox runat="server" ID="txtPassword" /></td>
    </tr>
    <tr>
        <td colspan="2" align="center">
            <asp:Button Text="Sign Up" runat="server" OnClick="OnSignUp" />
        </td>
    </tr>
</table>
<hr />
<table>
    <tr>
        <td>UserId</td>
        <td><asp:TextBox runat="server" ID="txtEmail" /></td>
    </tr>
    <tr>
        <td>Amount</td>
        <td><asp:TextBox runat="server" ID="txtAmount" /></td>
    </tr>
    <tr>
        <td colspan="2" align="center">
            <asp:Button ID="btnAdd" Text="Add Amount" runat="server" OnClick="OnAdd" />
        </td>
    </tr>
</table>
<hr />
<asp:GridView runat="server" ID="gvUserWallet" AutoGenerateColumns="false" EmptyDataText="No record.">
    <Columns>
        <asp:BoundField DataField="UserId" HeaderText="Email" />
        <asp:BoundField DataField="Amount" HeaderText="Amount" DataFormatString="{0:N0}" />
    </Columns>
</asp:GridView>

Namespaces

C#

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

VB.Net

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

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        BindWalletData();
    }
}
protected void OnSignUp(object sender, EventArgs e)
{
    int i = 0;
    // Insert on User Table.
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("INSERT INTO tblUser VALUES(@Id, @Password)"))
        {
            cmd.Parameters.AddWithValue("@Id", txtUserId.Text.Trim());
            cmd.Parameters.AddWithValue("@Password", txtPassword.Text.Trim());
            cmd.Connection = con;
            con.Open();
            i = cmd.ExecuteNonQuery();
            con.Close();
        }
    }

    if (i > 0)
    {
        // If new user inserted, Wallet table will be inserted with zero amount.
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand("INSERT INTO tblWallet VALUES(@Id, @Amount)"))
            {
                cmd.Parameters.AddWithValue("@Id", txtUserId.Text.Trim());
                cmd.Parameters.AddWithValue("@Amount", 0);
                cmd.Connection = con;
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
    BindWalletData();
}
protected void OnAdd(object sender, EventArgs e)
{
    decimal amount;
    object isExist;
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT Amount FROM tblWallet WHERE UserId = @Id"))
        {
            cmd.Connection = con;
            cmd.Parameters.AddWithValue("@Id", txtEmail.Text.Trim());
            con.Open();
            isExist = cmd.ExecuteScalar();
            con.Close();
        }
    }
    if (isExist != null)
    {
        amount = Convert.ToDecimal(isExist) + Convert.ToDecimal(txtAmount.Text.Trim());
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand("UPDATE tblWallet SET Amount = @Amout WHERE UserId = @Id"))
            {
                cmd.Parameters.AddWithValue("@Id", txtEmail.Text.Trim());
                cmd.Parameters.AddWithValue("@Amout", amount);
                cmd.Connection = con;
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
    else
    {
        ClientScript.RegisterClientScriptBlock(this.GetType(), "", "alert('User Not exist.')", true);
    }
    BindWalletData();
}
private void BindWalletData()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    string query = "SELECT * FROM tblWallet";
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand(query))
        {
            cmd.Connection = con;
            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                DataTable dt = new DataTable();
                sda.Fill(dt);
                gvUserWallet.DataSource = dt;
                gvUserWallet.DataBind();
            }
        }
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        BindWalletData()
    End If
End Sub

Protected Sub OnSignUp(ByVal sender As Object, ByVal e As EventArgs)
    Dim i As Integer = 0
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("INSERT INTO tblUser VALUES(@Id, @Password)")
            cmd.Parameters.AddWithValue("@Id", txtUserId.Text.Trim())
            cmd.Parameters.AddWithValue("@Password", txtPassword.Text.Trim())
            cmd.Connection = con
            con.Open()
            i = cmd.ExecuteNonQuery()
            con.Close()
        End Using
    End Using

    If i > 0 Then
        Using con As SqlConnection = New SqlConnection(constr)
            Using cmd As SqlCommand = New SqlCommand("INSERT INTO tblWallet VALUES(@Id, @Amount)")
                cmd.Parameters.AddWithValue("@Id", txtUserId.Text.Trim())
                cmd.Parameters.AddWithValue("@Amount", 0)
                cmd.Connection = con
                con.Open()
                cmd.ExecuteNonQuery()
                con.Close()
            End Using
        End Using
    End If

    BindWalletData()
End Sub

Protected Sub OnAdd(ByVal sender As Object, ByVal e As EventArgs)
    Dim amount As Decimal
    Dim isExist As Object
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT Amount FROM tblWallet WHERE UserId = @Id")
            cmd.Connection = con
            cmd.Parameters.AddWithValue("@Id", txtEmail.Text.Trim())
            con.Open()
            isExist = cmd.ExecuteScalar()
            con.Close()
        End Using
    End Using

    If isExist IsNot Nothing Then
        amount = Convert.ToDecimal(isExist) + Convert.ToDecimal(txtAmount.Text.Trim())
        Using con As SqlConnection = New SqlConnection(constr)
            Using cmd As SqlCommand = New SqlCommand("UPDATE tblWallet SET Amount = @Amout WHERE UserId = @Id")
                cmd.Parameters.AddWithValue("@Id", txtEmail.Text.Trim())
                cmd.Parameters.AddWithValue("@Amout", amount)
                cmd.Connection = con
                con.Open()
                cmd.ExecuteNonQuery()
                con.Close()
            End Using
        End Using
    Else
        ClientScript.RegisterClientScriptBlock(Me.[GetType](), "", "alert('User Not exist.')", True)
    End If

    BindWalletData()
End Sub

Private Sub BindWalletData()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Dim query As String = "SELECT * FROM tblWallet"
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand(query)
            cmd.Connection = con
            Using sda As SqlDataAdapter = New SqlDataAdapter(cmd)
                Dim dt As DataTable = New DataTable()
                sda.Fill(dt)
                gvUserWallet.DataSource = dt
                gvUserWallet.DataBind()
            End Using
        End Using
    End Using
End Sub

Screenshot