Static CRUD Operation In C#

Introduction to CRUD

CRUD - Create, Read, Update And Delete

In this article, you will learn how to make a static application that performs Select, Add, Update & Delete operations.

Let's start.

Step 1 - Add New Project

Open Visual Studio 2017 => Click Add Project => Select Web Application Template => Fill all required details.

Step 2

Select Web Application Template.

Step 3

Add new item.

Right click in project solution => Add => New Item

Step 4

Paste the below Html code under the body tag.

<form id="form1" runat="server">
<div style="display: flex; justify-content: center;">
<table border="1">
<tr>
<td>Employee ID</td>
<td>
<asp:TextBox ID="txtID" runat="server"></asp:TextBox>
</td>
<td>
<asp:RequiredFieldValidator ID="rfEmpId" runat="server" ControlToValidate="txtID" ErrorMessage="*" ForeColor="Red" ValidationGroup="grpemp"></asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td>Employee Name</td>
<td>
<asp:TextBox ID="txtName" runat="server"></asp:TextBox>
</td>
<td>
<asp:RequiredFieldValidator ID="rfEmpName" runat="server" ControlToValidate="txtName" ErrorMessage="*" ForeColor="Red" ValidationGroup="grpemp"></asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td>Gender</td>
<td>
<asp:DropDownList ID="ddlgender" runat="server">
<asp:ListItem>--Select--</asp:ListItem>
<asp:ListItem>Male</asp:ListItem>
<asp:ListItem>Female</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:RequiredFieldValidator ID="rfEmpgender" runat="server" InitialValue="--Select--" ControlToValidate="ddlgender" ErrorMessage="*" ForeColor="Red" ValidationGroup="grpemp"></asp:RequiredFieldValidator>
</td>
</tr>
<tr style="text-align: center;">
<td colspan="2">
<asp:Button ID="btnAdd" runat="server" Text="ADD" Style="cursor: pointer;" OnClick="btnAdd_Click" ValidationGroup="grpemp" CausesValidation="true" />
</td>
</tr>
</table>
</div>
<br />
<br />
<div style="display: flex; justify-content: center;">
<asp:GridView ID="gvemployee" runat="server" BackColor="#DEBA84" BorderColor="#DEBA84" BorderStyle="None" BorderWidth="1px" CellPadding="3" CellSpacing="2" OnSelectedIndexChanged="gvemployee_SelectedIndexChanged" OnRowDeleting="gvemployee_RowDeleting" AutoGenerateColumns="false">
<Columns>
<asp:TemplateField HeaderText="SELECT">
<itemtemplate>
<asp:LinkButton ID="LnkSelect" runat="server" CommandName="Select">Select</asp:LinkButton>
</itemtemplate>
</asp:TemplateField>
<asp:BoundField DataField="ID" HeaderText="EMPLOYEE ID" />
<asp:BoundField DataField="Name" HeaderText="EMPLOYEE NAME" />
<asp:BoundField DataField="Gender" HeaderText="GENDER" />
<asp:TemplateField HeaderText="DELETE">
<ItemTemplate>
<asp:LinkButton ID="LinkButton1" runat="server" CommandName="Delete" OnClientClick="return confirm('Are you sure to delete this employee?');">Delete</asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
<FooterStyle BackColor="#F7DFB5" ForeColor="#8C4510" />
<HeaderStyle BackColor="#A55129" Font-Bold="True" ForeColor="White" />
<PagerStyle ForeColor="#8C4510" HorizontalAlign="Center" />
<RowStyle BackColor="#FFF7E7" ForeColor="#8C4510" />
<%--<SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="White" />--%>
<SortedAscendingCellStyle BackColor="#FFF1D4" />
<SortedAscendingHeaderStyle BackColor="#B95C30" />
<SortedDescendingCellStyle BackColor="#F1E5CE" />
<SortedDescendingHeaderStyle BackColor="#93451F" />
</asp:GridView>
</div>
</form>

Step 5

Replace auto generated class code with the below code.

public partial class CRUD : System.Web.UI.Page
{
DataTable dtEmp = new DataTable("Employee");
protected void Page_Load(object sender, EventArgs e)
{
}
protected void btnAdd_Click(object sender, EventArgs e)
{
if (Page.IsValid)
{
if (btnAdd.Text == "ADD")
{
if (gvemployee.Rows.Count == 0)
{
dtEmp.Columns.Add("ID", typeof(String));
dtEmp.Columns.Add("Name", typeof(String));
dtEmp.Columns.Add("Gender", typeof(String));
DataRow dr = dtEmp.NewRow();
dr["ID"] = txtID.Text;
dr["Name"] = txtName.Text;
dr["Gender"] = ddlgender.SelectedValue;
dtEmp.Rows.Add(dr);
ViewState["EmployeeTable"] = dtEmp;
gvemployee.DataSource = dtEmp;
gvemployee.DataBind();
}
else
{
dtEmp = (DataTable)ViewState["EmployeeTable"];
DataRow dr;
dr = dtEmp.Select("ID='" + txtID.Text + "'").FirstOrDefault();
if (dr != null)
{
ClientScript.RegisterStartupScript(this.GetType(), "employeealert", "alert('Employee ID already exist');", true);
return;
}
dr = dtEmp.NewRow();
dr["ID"] = txtID.Text;
dr["Name"] = txtName.Text;
dr["Gender"] = ddlgender.SelectedValue;
dtEmp.Rows.Add(dr);
ViewState["EmployeeTable"] = dtEmp;
gvemployee.DataSource = dtEmp;
gvemployee.DataBind();
}
}
else
{
dtEmp = (DataTable)ViewState["EmployeeTable"];
DataRow dr = dtEmp.Select("ID='" + txtID.Text + "'").FirstOrDefault();
if (dr != null)
{
dr["Name"] = txtName.Text;
dr["Gender"] = ddlgender.SelectedValue;
}
gvemployee.DataSource = dtEmp;
gvemployee.DataBind();
txtID.ReadOnly = false;
btnAdd.Text = "ADD";
}
Clear();
}
}
protected void gvemployee_SelectedIndexChanged(object sender, EventArgs e)
{
txtID.Text = gvemployee.SelectedRow.Cells[1].Text;
txtName.Text = gvemployee.SelectedRow.Cells[2].Text;
ddlgender.SelectedValue = gvemployee.SelectedRow.Cells[3].Text;
txtID.ReadOnly = true;
btnAdd.Text = "Update";
}
public void Clear()
{
txtID.Text = "";
txtName.Text = "";
ddlgender.SelectedIndex = 0;
}
protected void gvemployee_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
dtEmp = (DataTable)ViewState["EmployeeTable"];
dtEmp.Rows.RemoveAt(e.RowIndex);
gvemployee.DataSource = dtEmp;
gvemployee.DataBind();
}
}