Give validation to textbox that accepts min 6 charecters and max 12 charecters in Asp.net

For that add textbox control with the property MaxLength=12 and add RegularExpressionValidator with RegularExpression.

<asp:TextBox ID="TxtName" runat="server" MaxLength="12" Width="200px"></asp:TextBox>

<br />

<asp:RegularExpressionValidator

ID="RegularExpressionValidator1" 

ControlToValidate="TxtName"                                

ValidationExpression="(?=^.{6,12}$)(?=.*\d)(?=.*\W+)(?![.\n]).*$"

runat="server"

Text="Password must have minimum 6 characters & maximum 12 characters"></asp:RegularExpressionValidator>

Fill Years to Dropdownlist dynamically with some range in Asp.net

Filling Dropdownlist dynamically with the range of 1900 to this Year, for that

write the following code in PageLoad:

protected void Page_Load(object sender, EventArgs e)

    {

        if (!Page.IsPostBack)

        {

             int thisYear = Convert.ToInt32(System.DateTime.Now.Year);

            for (int i = 1999; i <= thisYear; i++)

            {

                ddlYear.Items.Add(new ListItem(i.ToString(), i.ToString()));

            }

            ListItem lsitem = new ListItem("Select Year", "0");

            ddlYear.Items.Insert(0, lsitem);

        }

    }

Fill Month Names and values to Dropdownlist dynamically in Asp.net

Add the following Namespace on the top for DateTimeFormatInfo:

using System.Globalization;

then write the following code in PageLoad:

protected void Page_Load(object sender, EventArgs e)

  {

               

   if (!Page.IsPostBack)

  {

        DateTimeFormatInfo info = DateTimeFormatInfo.GetInstance(null);

        for (int i = 0; i < 12; i++)

        {

            ddlMonth.Items.Add(new ListItem(info.MonthNames[i], i.ToString()));

           

        }

        ListItem lsitem = new ListItem("Select Month", "0");

        ddlMonth.Items.Insert(0, lsitem);

    }

  }