ASP.NET - Basic Controls

Syntax#

• <asp:Button ID=“Button1” runat=“server” onclick=“Button1_Click” Text=“Click” / > <asp:TextBox ID=“txtstate” runat=“server”>
• </asp:TextBox> <asp:CheckBox ID= “chkoption” runat= “Server”> </asp:CheckBox> <asp:RadioButton ID= “rdboption” runat= “Server”> </asp: RadioButton>
• <asp:ListBox ID=“ListBox1” runat=“server” AutoPostBack=“True”
  OnSelectedIndexChanged=“ListBox1_SelectedIndexChanged”> </asp:ListBox>
• <asp:DropDownList ID=“DropDownList1” runat=“server” AutoPostBack=“True”
  OnSelectedIndexChanged=“DropDownList1_SelectedIndexChanged”> </asp:DropDownList>
• <asp:RadioButtonList ID=“RadioButtonList1” runat=“server” AutoPostBack=“True”
  OnSelectedIndexChanged=“RadioButtonList1_SelectedIndexChanged”> </asp:RadioButtonList>
• <asp:CheckBoxList ID=“CheckBoxList1” runat=“server” AutoPostBack=“True”
  OnSelectedIndexChanged=“CheckBoxList1_SelectedIndexChanged”> </asp:CheckBoxList>
• <asp:BulletedList ID=“BulletedList1” runat=“server”> </asp:BulletedList>
• <asp:HyperLink ID=“HyperLink1” runat=“server”> HyperLink </asp:HyperLink> <asp:Image ID=“Image1” runat=“server”>

Text Boxes and Labels

Text box controls are typically used to accept input from the user. A text box control can accept one or more lines of text depending upon the settings of the TextMode attribute.

Label controls provide an easy way to display text which can be changed from one execution of a page to the next. If you want to display text that does not change, you use the literal text.

Basic syntax of text control:

<asp:TextBox ID="txtstate" runat="server" ></asp:TextBox>

Common Properties of the Text Box and Labels:

Check Boxes and Radio Buttons

A check box displays a single option that the user can either check or uncheck and radio buttons present a group of options from which the user can select just one option.

To create a group of radio buttons, you specify the same name for the GroupName attribute of each radio button in the group. If more than one group is required in a single form, then specify a different group name for each group.

If you want check box or radio button to be selected when the form is initially displayed, set its Checked attribute to true. If the Checked attribute is set to true for multiple radio buttons in a group, then only the last one is considered as true.

Basic syntax of check box:

<asp:CheckBox ID= "chkoption" runat= "Server"> </asp:CheckBox>

Basic syntax of radio button:

<asp:RadioButton ID= "rdboption" runat= "Server"> </asp: RadioButton>

Common properties of check boxes and radio buttons:

List Controls

ASP.NET provides the following controls

• Drop-down list
• List box
• Radio button list
• Check box list
• Bulleted list

These control let a user choose from one or more items from the list. List boxes and drop-down lists contain one or more list items. These lists can be loaded either by code or by the ListItemCollection editor.

Basic syntax of list box control:

<asp:ListBox ID="ListBox1" runat="server" AutoPostBack="True"    OnSelectedIndexChanged="ListBox1_SelectedIndexChanged">
</asp:ListBox>

Basic syntax of drop-down list control:

<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True"   OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>

Common properties of list box and drop-down Lists:

It is important to notes that:

• To work with the items in a drop-down list or list box, you use the Items property of the control. This property returns a ListItemCollection object which contains all the items of the list.
• The SelectedIndexChanged event is raised when the user selects a different item from a drop-down list or list box.

Radio Button list and Check Box list

A radio button list presents a list of mutually exclusive options. A check box list presents a list of independent options. These controls contain a collection of ListItem objects that could be referred to through the Items property of the control.

Basic syntax of radio button list:

<asp:RadioButtonList ID="RadioButtonList1" runat="server" AutoPostBack="True" 
   OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged">
</asp:RadioButtonList>

Basic syntax of check box list:

<asp:CheckBoxList ID="CheckBoxList1" runat="server" AutoPostBack="True" 
   OnSelectedIndexChanged="CheckBoxList1_SelectedIndexChanged">
</asp:CheckBoxList>

Common properties of check box and radio button lists:

Bulleted lists and Numbered lists

The bulleted list control creates bulleted lists or numbered lists. These controls contain a collection of ListItem objects that could be referred to through the Items property of the control.

Basic syntax of a bulleted list:

<asp:BulletedList ID="BulletedList1" runat="server">
</asp:BulletedList>

Common properties of the bulleted list:

HyperLink Control

The HyperLink control is like the HTML element.

<asp:HyperLink ID="HyperLink1" runat="server">
   HyperLink
</asp:HyperLink>

<asp:Image ID="Image1" runat="server">