Web developers can use the ImageMap control to create an image that contains defined hot spot regions. When users click a hot spot region, the control can either generate a postback to the server or navigate to a specified URL. This This control can also be used to generate a postback to the server and run specific code based on the hot spot region that was clicked.

Web developers should use the ImageUrl property to determine the path to the image to display for the ImageMap control. They can define any number of HotSpot objects within an ImageMap control and they can use the CircleHotSpot, RectangleHotSpot, and PolygonHotSpot classes to define hot spot regions. Alternatively, they can derive from the abstract HotSpot class to define their own custom hot spot object.

There are two ways to determine the behavior of a HotSpot object in an ImageMap control when the HotSpot is clicked:

–          To use the HotSpotMode property on the ImageMap control
–          To use the HotSpotMode property on an individual HotSpot object.

These properties can be set by using one of the HotSpotMode enumeration values. If both properties are set, the HotSpotMode property specified on each individual HotSpot object takes precedence over the HotSpotMode property on the ImageMap control.

 

To navigate to a URL, Web developers should set:

–          the ImageMap.HotSpotMode property
–          the HotSpot.HotSpotMode property to HotSpotMode.Navigate.

They should use the NavigateUrl property to determine the URL to navigate to.

 

To generate a postback to the server, Web developers should set:

–          the ImageMap.HotSpotMode property
–          the HotSpot.HotSpotMode property to HotSpotMode.Postback.

They should use the PostBackValue property to specify a name for the hot spot region. This name will be passed in the ImageMapEventArgs event data when a postback event occurs. When a postback HotSpot is clicked, the Click event is raised. To programmatically control the actions performed when a postback HotSpot is clicked, Web developers should provide an event handler for the Click event.

To cause all HotSpot objects in an ImageMap control to have the same behavior, Web developers should use the ImageMap.HotSpotMode property to specify the behavior. Then, they should set the HotSpot.HotSpotMode property on each individual HotSpot object to HotSpotMode.NotSet or do not specify a value for the HotSpot.HotSpotMode property.

To specify different behaviors for HotSpot objects in an ImageMap, Web developers should set the HotSpot.HotSpotMode property on each individual HotSpot object to either HotSpotMode.Navigate or HotSpotMode.PostBack.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in System.Web.dll)

Property Description Supported in .NET version
AccessKey This property returns or sets the access key that allows software developer to quickly navigate to the Web server control. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Adapter This property gets the browser-specific adapter for the control. 2.0, 3.0, 3.5, 4.0
AlternateText This property is used to get or set the alternate text displayed in the Image control when the image is unavailable. Browsers that support the ToolTips feature display this text as a ToolTip. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
AppRelativeTemplateSourceDirectory

 

Software developer can use this property to set or get the application-relative path to the page or user control that contains the current control.  If the web page is installed in https://www.somesite.com/apps/application1 the property will return “~/application1”. 2.0, 3.0, 3.5, 4.0
Attributes This property is a collection which contains a collection of all attributes declared in the opening tag of a Web server control. Software developer can control programmatically the attributes associated with a Web server control. He/she can add or remove attributes to/from the collection. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
BackColor The property is used to specify the background color of the Web server control. Software developer can set it using a System.Drawing..::.Color object. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
BindingContainer Software developer can’t use this property directly from his/her code, because it supports the .NET Framework infrastructure.  The property contains a reference to the Control object which contains data-binding information for the current control. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
BorderColor The property is used to specify the border color of the Web server control. Software developer can set it using a System.Drawing..::.Color object. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
BorderStyle Specifies the type of the control’s border. Software developer can choose one of the values from the BorderStyle enumeration – Dashed, Dotted, Double, Grrove, Ridge, Inset, Outset, Solid and None. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
BorderWidth Specifies the size of the control’s border.  When software developer sets this property he/she should use combination of a numeric value followed by type of measurement: px (for pixels) or % (for percentage) and so on. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ChildControlsCreated Gets a true value that indicates whether the server control’s child controls have been created. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ClientID Returns the server control identifier generated by ASP.NET. The ClientID value is generated by concatenating the ID value of the control and the UniqueID value of its parent control. If the ID value of the control is not specified, an automatically generated value is used. Each part of the generated ID is separated by an underscore character (_). 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ClientIDSeparator The ClientID value is generated by concatenating the ID value of the control and the UniqueID value of its parent control. Each part of the generated ID property is separated by the ClientIDSeparator property value. The value always returns an underscore (_). 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Context Software developer can use this property to access the HttpContext object for the current Web request. Using properties of the object software developer can access objects Application, Session, Request, Response, etc. which contain information about the current HTTP request. The object provides methods that allow him to get configuration information and to set or clear errors related to the request. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Controls This property allows software developer to access programmatically to the instance of the ControlCollection class for any server control. Using it he/she can add/remove controls to/from the collection or iterate through the server controls in the collection. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ControlStyle This property is used to encapsulate all properties of the WebControl class that specify the appearance of the control, such as BorderColor and Font. This property is used primarily by control developers. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ControlStyleCreated This property is used primarily by control developers. Returns a true value if a Style object has been created for the ControlStyle property; otherwise false. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
CssClass Software developer can use this property to specify the CSS class to render on the client for the Web Server control. This property will render on browsers for all controls. On browsers that do not support CSS, setting the CssClass property will have no effect. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
DescriptionUrl This property is inherited from Image and is used to get or set the location to a detailed description for the image.   Its default value is an empty string (“”).  The DescriptionUrl property specifies an HTML file that provides additional details for the image. The DescriptionUrl property renders as the longdesc attribute for the image control. If the DescriptionUrl property is not set, or is set to an empty string (“”), the Image control renders without the longdesc attribute. The DescriptionUrl property is optional, but it can enhance the accessibility of the Web page for text-only browsers and screen readers. Browsers can use the detailed text description to convey important concepts in place of, or in addition to, the visual image. 2.0, 3.0, 3.5, 4.0
DesignMode This property returns true to indicate that the control is being used in the context of a designer. Software developer’s custom controls can use this property when design-time behavior is different than run-time behavior. 2.0, 3.0, 3.5, 4.0
Enabled Software developer should set this property to true when he/she wants to specify or determine whether a control is functional. When developer sets to false, the control appears dimmed, preventing any input from being entered in the control. Notes:

  • Not all browsers support this property. Dimming and locking the control only works in browsers that are compatible with Microsoft Internet Explorer version 4 and later.
  • In a custom composite control, this behavior does not apply to controls that have not yet created their child controls.
  • A disabled control can support postbacks. It is possible for a user who is viewing the page with a disabled control to craft a request that submits a postback that is processed by the page.
1.0,1.1, 2.0, 3.0, 3.5, 4.0
EnableTheming This property overrides Control. EnableTheming.

The property indicates whether themes are enabled for a specified control. When the property’s value is true, the application’s theme directory is searched for control skins to apply. If for the particular control skin does not exist in the directory, skins are not applied. When the property’s value is false, the theme directory is not searched and the contents of the SkinID property are not used.

2.0, 3.0, 3.5, 4.0
EnableViewState Software developer must enable view state for the server control setting its value to true if he/she wants to maintain its state across HTTP requests. Sometimes is better to set value of this property to false if for example Web application is loading a database request into a server control. In this case application performance will be improved. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Events This read-only property returns a list of event handler delegates for the control. The type of this property is EventHadlerList, which uses a linear search algorithm to find entries in the list of delegates. When the list of delegates is large, finding entries with this property will be slow, because a linear search algorithm is inefficient when working with a large number of entries. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Font Software developer can use this property to specify the font properties of the Web Server control. This property includes subproperties that can be accessed declaratively in the form of Property-Subproperty (for example Font-Bold) or programmatically in the form of Property.Subproperty (for example Font.Bold).

All but one subproperty will render in browsers prior to Microsoft Internet Explorer version 4 for all controls. They are: Bold, Italic, Name, Names, Strikeout, Underline, and Size (but only named font sizes, such as Small, Smaller, and so on, will work).

 

1.0,1.1, 2.0, 3.0, 3.5, 4.0
ForeColor Software developer can use this property to to specify the foreground color of the Web server control. The foreground color is usually the color of the text. This property will render on browsers earlier than Microsoft Internet Explorer version 4 for all controls, except the Image, AdRotator, HyperLink and LinkButton. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
GenerateEmptyAlternateText This property is inherited from Image and gets or sets a value indicating whether the control generates an alternate text attribute for an empty string value. Its default value is false. Its value is true if the control generates the alternate text attribute for an empty string value; otherwise, false.  By default, when the AlternateText property is not set, the Image control does not include the alt attribute to specify the alternate text in the control rendering. Web developer should set the property value to true to always include the alternate text attribute in rendered output for the Image control. 2.0, 3.0, 3.5, 4.0
HasAttributes This property returns true when the WebControl instance has attribute name/value pairs. The attribute pairs can be set either in the property or in the view state. 2.0, 3.0, 3.5, 4.0
HasChildViewState Software developer can use this property to verify that any child controls of the server control are storing view-state information. Using it in this way he/she can avoid unnecessary calls to the ClearChildViewState method. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Height This property is used to specify the height of the Web server control. When software developer sets this property he/she should use combination of a numeric value followed by type of measurement: px (for pixels) or % (for percentage) and so on.This property does not render for all controls in browsers earlier than Microsoft Internet Explorer version 4. Controls that do not render this property in earlier browsers include Label, HyperLink, LinkButton, and any validation controls. The CheckBoxList, RadioButtonList and DataList also do not render this property in earlier browsers when their RepeatLayout property is set to RepeatLayout.Flow. Furthermore, only unit types of Pixel and Percentage are supported in earlier browsers. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
HotSpotMode This property is used to get or set the default behavior for the HotSpot objects of an ImageMap control when the HotSpot objects are clicked. This property is set using one of the HotSpotMode enumeration values:

– Inactive – The HotSpot object does not have any behavior. Web developers can use this value to create an inactive hot spot within a larger active hot spot. This option is provided to allow them to create more complex hot spot zones within an ImageMap control.

– NotSet – The HotSpot object uses the behavior set by the ImageMap control’s HotSpotMode property. If the ImageMap control does not define the behavior, the HotSpot objects all navigate to a URL.

– Navigate – The HotSpot objects navigate to a URL. Web developers should use the NavigateUrl property to specify the URL to navigate to.

– PostBack – The HotSpot objects generate a postback to the server. Web developers should use the PostBackValue property to specify the name of the hot spot region. This name will be passed in the ImageMapEventArgs event data when a postback event occurs. When a postback HotSpot is clicked, the Click event is raised. To programmatically control the actions performed when a postback HotSpot is clicked, Web developers should provide an event handler for the Click event.

2.0, 3.0, 3.5, 4.0
HotSpots This property returns a collection of HotSpot objects that represents the defined hot spot regions in an ImageMap control.  Web developers can use the HotSpots property to add, insert, remove, and retrieve HotSpot objects. 2.0, 3.0, 3.5, 4.0
ID Web developers can set this property by declaring ID attribute in the opening tag of an ASP.NET server control. Another possible way to set it is programmatically. If this property is not specified for a server control, either declaratively or programmatically, Web developer can obtain a reference to the control through its parent control’s Controls property. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
IdSeparator Software developer can’t use this property directly from his/her code, because it supports the .NET Framework infrastructure.   The character contained in this property ( by default $ ) is used to separate the control identifiers for child controls. The ID separator character is appended to the ID property. 2.0, 3.0, 3.5, 4.0
ImageAlign This property gets or sets the alignment of the Image control in relation to other elements on the Web page. Its default value is NotSet. The possible alignments are:

–          Left – The image is aligned on the left edge of the Web page with text wrapping on the right.

–          Right – The image is aligned on the right edge of the Web page with text wrapping on the left.

–          Baseline – The lower edge of the image is aligned with the lower edge of the first line of text.

–          Top – The upper edge of the image is aligned with the upper edge of the highest element on the same line.

–          Middle – The middle of the image is aligned with the lower edge of the first line of text.

–          Bottom – The lower edge of the image is aligned with the lower edge of the first line of text.

–          AbsBottom – The lower edge of the image is aligned with the lower edge of the largest element on the same line.

–          AbsMiddle – The middle of the image is aligned with the middle of the largest element on the same line.

–          TextTop – The upper edge of the image is aligned with the upper edge of the highest text on the same line.

1.0,1.1, 2.0, 3.0, 3.5, 4.0
ImageUrl Returns or sets the location of an image to display in the Image control.  Web developers can use a relative or an absolute URL. A relative URL relates the location of the image to the location of the Web page without specifying a complete path on the server. The path is relative to the location of the Web page. This makes it easier to move the entire site to another directory on the server without updating the code. An absolute URL provides the complete path, so moving the site to another directory requires that you update the code. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
IsChildControlStateCleared This property has value true if children of this control do not use control state; otherwise, false. 2.0, 3.0, 3.5, 4.0
IsEnabled This property returns true if the Enabled property is true for this control and any containing controls. 2.0, 3.0, 3.5, 4.0
IsTrackingViewState This property returns value true if the control is marked to save changes to its view state; otherwise, false.

 

1.0,1.1, 2.0, 3.0, 3.5, 4.0
IsViewStateEnabled This property returns value true if view state is enabled for the control; otherwise false.  View state can be enabled at the page, container, or control level. When view state is disabled at the page or container level, view state is disabled for all controls contained by the page or container. The property indicates whether view state is enabled by pages, containers, or controls. In some cases it is possible values for the EnableViewState property and the IsViewStateEnabled property to be different. For example, if the Page containing the control has view state disabled, the EnableViewState property can be true while the IsViewStateEnabled property is false. Notes: Developers will set the EnableViewState property to indicate whether they are using view state with your control. Web developers can use this property in their code to determine whether view state is enabled for their control and all containers. 2.0, 3.0, 3.5, 4.0
LoadViewStateByID This property returns value true if the control loads its view state by ID; otherwise, false. Its default value is false. 2.0, 3.0, 3.5, 4.0
NamingContainer Using this property software developer can get a reference to the server control’s naming container, which creates a unique namespace for differentiating between server controls with the same Control.ID property value. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Page Provides a reference to the web page that contains this control as a System.Web.UI.Page object.  This property’s value reflects the name of the .aspx file that contains the server control. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Parent This property provides a reference to the control that contains this control. If the control is placed on the page directly (rather than inside another control), it will return a reference to the page object. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Site Using this property software developer can get information about the container that hosts the current control when rendered on a design surface.  A site binds a Component object to a Container object and enables communication between the two. It also provides a way for the container to manage its components. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
SkinID This property overrides Control.SkinID.

Web developer can get or set the skin to apply to the control.  Skins available to a control are contained in one or more skin files in a theme directory. The SkinID property specifies which of these skins to apply to the control. A skin is specific to a particular control i.e. software developer cannot share skin setting between controls of different types. If developer does not set the SkinID property, a control uses the default skin if one is defined.

2.0, 3.0, 3.5, 4.0
Style Web developer can use this property to get a collection of text attributes that will be rendered as a style attribute on the outer tag of the Web server control. This property will render on all browsers for all controls. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
TabIndex With this number software developer can control the tab order. The control with a TabIndex of  zero has the focus when the page first loads. If end user presses Tab his/her focus will be moved to the control with the next lowest TabIndex. This property is available only in Internet Explorer 4.0 and higher. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
TagKey Gets the HtmlTextWriterTag value that corresponds to this Web server control. This property is used primarily by control developers 1.0,1.1, 2.0, 3.0, 3.5, 4.0
TagName Web developers can use this property to get the name of the control tag. This property is used primarily by control developers. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Target This property gets or sets the name of the browser window or frame that displays the contents of the Web page linked to when the ImageMap control is clicked. The default value is an empty string (“”), which refreshes the window or frame with focus. The Target value must begin with a letter in the range of A to Z (case-insensitive), except for the following special values, which begin with an underscore:

– _blank – Renders the content in a new window without frames

– _parent – Renders the content in the immediate frameset parent.

– _search – Renders the content in the search pane. Some browsers do not support this value.

– _self – Renders the content in the frame with focus.

– _top – Renders the content in the full window without frames.

The Target property renders as a target attribute. The target attribute on anchor elements is not allowed in the XHTML 1.1 document type definition. Web developers should not set the Target property if the rendered output for the ImageMap must be XHTML 1.1 compliant.

2.0, 3.0, 3.5, 4.0
TemplateControl This property is used to get or set a reference to the template that contains this control. 2.0, 3.0, 3.5, 4.0
TemplateSourceDirectory Software developer can use this property to get the path to the page or user control that contains the current control.  If the web page is installed in https://www.somesite.com/apps/application1 the property will return “apps/application1”. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ToolTip This property displays a text message when the end users hover the mouse above the control. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
UniqueID This property can be used to get the unique, hierarchically qualified identifier for the server control. This property differs from the ID property, in that the UniqueID property includes the identifier for the server control’s naming container. This identifier is generated automatically when a page request is processed. This property is particularly important in differentiating server controls contained within a data-binding server control that repeats as Repeater, DataList, DetailsView, FormView, and GridView Web server controls. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ViewState Web developers can use this property to get a dictionary of state information that allows them to save and restore the view state of a server control across multiple requests for the same page. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
ViewStateIgnoresCase This property returns true if StateBag object is insensitive; otherwise, false. Its default value is false. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Visible Web developers can use this property to get or set a value that indicates whether a server control is rendered as UI on the page. If the control is visible on the page this property will has value true; otherwise false. 1.0,1.1, 2.0, 3.0, 3.5, 4.0
Width This property is used to specify the width of the Web server control. When software developer sets this property he/she should use combination of a numeric value followed by type of measurement: px (for pixels) or % (for percentage) and so on.This property does not render for all controls in browsers earlier than Microsoft Internet Explorer version 4. Controls that do not render this property in earlier browsers include Label, HyperLink, LinkButton, and any validation controls. The CheckBoxList, RadioButtonList and DataList also do not render this property in earlier browsers when their RepeatLayout property is set to RepeatLayout.Flow. Furthermore, only unit types of Pixel and Percentage are supported in earlier browsers. 1.0,1.1, 2.0, 3.0, 3.5, 4.0