CREATE TABLE [dbo].[Employee] (  
    [EmpId]     INT          NOT NULL,  
    [FirstName] VARCHAR (20) NOT NULL,  
    [LastName]  VARCHAR (20) NOT NULL,  
    [City]      VARCHAR (20) NOT NULL,  
    PRIMARY KEY CLUSTERED ([EmpId] ASC)  
);

<asp:BoundField DataField="FirstName" HeaderText="First Name" />

<asp:TemplateField>  
                    <ItemTemplate>  
                        <asp:CheckBox ID="chkDel" runat="server" />  
                    </ItemTemplate>  
                </asp:TemplateField>

<asp:Button ID="btnDeleteRecord" runat="server" OnClick="btnDeleteRecord_Click" Text="Delete"  />

function DeleteConfirm() 
        {  
            var Ans = confirm("Do you want to Delete Selected Employee Record?");  
            if (Ans)
            {  
                return true;  
            }  
            else 
            {  
                return false;  
            }  
        }

protected void Page_Load(object sender, EventArgs e)  
{  
    if(!IsPostBack)  
    {  
        //Displaying the Data  
        showData();  
        //Adding an Attribute to Server Control(i.e. btnDeleteRecord)  
        btnDeleteRecord.Attributes.Add("onclick", "javascript:return DeleteConfirm()");  
    }  
}

//Method for Displaying Data  
protected void showData()  
{  
    DataTable dt = new DataTable();  
    SqlConnection con = new SqlConnection(cs);  
    SqlDataAdapter adapt = new SqlDataAdapter("select * from Employee",con);  
    con.Open();  
    adapt.Fill(dt);  
    con.Close();  
    GridView1.DataSource = dt;  
    GridView1.DataBind();  
}

protected void DeleteRecord(int empid)  
{  
    SqlConnection con = new SqlConnection(cs);  
    SqlCommand com = new SqlCommand("delete from Employee where EmpId=@ID",con);  
    com.Parameters.AddWithValue("@ID",empid);  
    con.Open();  
    com.ExecuteNonQuery();  
    con.Close();  
}

protected void btnDeleteRecord_Click(object sender, EventArgs e)  
{  
    foreach (GridViewRow grow in GridView1.Rows)  
    {  
        //Searching CheckBox("chkDel") in an individual row of Grid  
        CheckBox chkdel = (CheckBox)grow.FindControl("chkDel");  
        //If CheckBox is checked than delete the record with particular empid  
        if(chkdel.Checked)  
        {  
            int empid = Convert.ToInt32(grow.Cells[1].Text);  
            DeleteRecord(empid);  
        }  
    }  
    //Displaying the Data in GridView  
    showData();  
}

@Number

@code {
    [Parameter]
    public string Number { get; set; }

    protected override Task OnInitializedAsync()
    {
        var persianDic = new Dictionary<char, char>
        {
            {'0','۰'},
            {'1','۱'},
            {'2','۲'},
            {'3','۳'},
            {'4','۴'},
            {'5','۵'},
            {'6','۶'},
            {'7','۷'},
            {'8','۸'},
            {'9','۹'},

        };
        var number = Number.ToString();
        var ech = number.ToCharArray();
        for (int i = 0; i < ech.Length; i++)
        {
            persianDic.TryGetValue(ech[i], out char pch);
            if (pch == null)
                continue;
            ech[i] = pch;
        }
        Number = new string(ech);
        return base.OnInitializedAsync();
    }
}

... 
@foreach (var item in _items)
                {
                    <tr>
                        <td class="h6 text-color-1">@item.Title</td>
                        <td> <PersianNumber Number="@item.Price.ToString()"/> ریال</td>
                    </tr>
                }
...

window.onbeforeunload = function (e) {
    $.connection.hub.stop();
};