Update multiple rows in database using Linq query without looping in ASP.Net

Hi irfanextc,

Please take reference the below code and correct your code.

SQL

CREATE TABLE [dbo].[UsersDetails](
	[ID] [int] IDENTITY(1,1) NOT NULL,
	[FirstName] [varchar](100) NULL,
	[LastName] [varchar](200) NULL,
	[Age] [int] NULL,
	[Education] [varchar](200) NULL,
	[Hobbies] [varchar](100) NULL,
	[Sex] [varchar](100) NULL,
 CONSTRAINT [PK_UsersDetails] PRIMARY KEY CLUSTERED 
(
	[ID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

HTML

<asp:TextBox ID="txtSex" runat="server"></asp:TextBox>
<asp:Button ID="btnUpdateSex" runat="server" OnClick="Update" Text="Update" /><br />
<asp:GridView ID="gvUsersDetails" runat="server" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="FirstName" HeaderText="FirstName" />
        <asp:BoundField DataField="LastName" HeaderText="LastName" />
        <asp:BoundField DataField="Age" HeaderText="Age" />
        <asp:BoundField DataField="Sex" HeaderText="Sex" />
    </Columns>
</asp:GridView>

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindUserDetails();
    }
}

private void BindUserDetails()
{
    TestEntities entity = new TestEntities();
    var user = (from p in entity.UsersDetails
                select p);
    this.gvUsersDetails.DataSource = user;
    this.gvUsersDetails.DataBind();
}
protected void Update(object sender, EventArgs e)
{
    TestEntities entity = new TestEntities();
    (from u in entity.UsersDetails
        select u).ToList().ForEach(x => x.Sex = txtSex.Text);
    entity.SaveChanges();
    this.BindUserDetails();
}

Screenshot