/// <summary>
/// This is used to add a dynamic image area on the initial page load
/// </summary>
/// <param name="sender">The sender of the event</param>
/// <param name="e">The event arguments</param>
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
lblEnabledMsg.Text = "Image map enabled";
// Add a dynamic image area. This is only created once when the page is first loaded. On post
// backs, the area is recreated from view state.
ImageAreaRectangle r = new ImageAreaRectangle(new Rectangle(40, 57, 20, 20));
r.Action = AreaClickAction.PostBack;
r.ToolTip = "Area 5 (Dynamically added)";
r.AccessKey = "5";
r.Attributes.Add("onmouseover", "javascript: IM_Highlight(5);");
r.Attributes.Add("onmouseout", "javascript: IM_Highlight(0);");
// Tell the item to mark all properties as dirty so that it is restored entirely from view state
// on post backs. If not done, you must recreate the area on post backs.
r.MarkAsDirty();
imClickMap.Areas.Add(r);
}
// The Visual Studio designer loses the custom attributes on the image area controls in the HTML when
// the collection editor is used. This happens to ListItem objects in controls such as the ListBox
// and DropDown controls too. The only workaround is to set such attributes in code as shown below
// when the page loads.
((ImageAreaBase)imClickMap.Areas[0]).Attributes.Add("onmouseover", "javascript: IM_Highlight(1);");
((ImageAreaBase)imClickMap.Areas[0]).Attributes.Add("onmouseout", "javascript: IM_Highlight(0);");
((ImageAreaBase)imClickMap.Areas[1]).Attributes.Add("onmouseover", "javascript: IM_Highlight(2);");
((ImageAreaBase)imClickMap.Areas[1]).Attributes.Add("onmouseout", "javascript: IM_Highlight(0);");
((ImageAreaBase)imClickMap.Areas[2]).Attributes.Add("onmouseover", "javascript: IM_Highlight(3);");
((ImageAreaBase)imClickMap.Areas[2]).Attributes.Add("onmouseout", "javascript: IM_Highlight(0);");
((ImageAreaBase)imClickMap.Areas[3]).Attributes.Add("onmouseover", "javascript: IM_Highlight(4);");
((ImageAreaBase)imClickMap.Areas[3]).Attributes.Add("onmouseout", "javascript: IM_Highlight(0);");
}
//=====================================================================
/// <summary>
/// Constructor
/// </summary>
public ImageMapEventsForm()
{
InitializeComponent();
// This is used to format text for various image areas
sfFormat = new StringFormat();
sfFormat.Alignment = StringAlignment.Center;
sfFormat.LineAlignment = StringAlignment.Center;
sfFormat.HotkeyPrefix = HotkeyPrefix.Show;
// A couple of fonts for some of the image areas
buttonFont = new Font("Microsoft Sans Serif", 7.8f, FontStyle.Bold);
hyperlinkFont = new Font("Microsoft Sans Serif", 7.8f, FontStyle.Underline);
// Get the image for the "buttons" and define the attributes used to given them their various draw
// state effects.
imgFiller = new Bitmap(GetType(), "ImageMapEventsForm.Filler.png");
// Image attributes used to lighten normal buttons
cmNormal = new ColorMatrix();
cmNormal.Matrix33 = 0.5f;
iaNormal = new ImageAttributes();
iaNormal.SetColorMatrix(cmNormal, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
// Image attributes that lighten and desaturate disabled buttons
cmDisabled = new ColorMatrix();
cmDisabled.Matrix00 = cmDisabled.Matrix01 = cmDisabled.Matrix02 = cmDisabled.Matrix10 =
cmDisabled.Matrix11 = cmDisabled.Matrix12 = cmDisabled.Matrix20 = cmDisabled.Matrix21 =
cmDisabled.Matrix22 = 0.33f;
cmDisabled.Matrix33 = 0.5f;
iaDisabled = new ImageAttributes();
iaDisabled.SetColorMatrix(cmDisabled, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
// Hook up the event handlers. Since they are not accessible in the designer, we must do it
// manually. Hang on to the references as we use them fairly often in here.
areaOwnerDrawOnOff = (ImageAreaRectangle)imMap.Areas[0];
areaOwnerDrawOnOff.Click += areaOwnerDrawOnOff_Click;
areaOwnerDrawOnOff.DrawImage += OwnerDrawOnOff_DrawImage;
areaVisitWebSite = (ImageAreaRectangle)imMap.Areas[3];
areaVisitWebSite.DrawImage += VisitWebSite_DrawImage;
areaVisitWebSite.DoubleClick += VisitWebSite_DoubleClick;
// The same draw event handler is used for the three "buttons". The image map Click event handles
// the area click events.
ImageAreaBase a = (ImageAreaBase)imMap.Areas[4];
a.DrawImage += Button_DrawImage;
a = (ImageAreaBase)imMap.Areas[5];
a.DrawImage += Button_DrawImage;
a = (ImageAreaBase)imMap.Areas[6];
a.DrawImage += Button_DrawImage;
// These two just demonstrate mouse and focus event handling by the image areas
a = (ImageAreaBase)imMap.Areas[1];
a.DrawImage += MouseArea_DrawImage;
a.MouseEnter += MouseArea_MouseEnter;
a.MouseDown += MouseArea_MouseDown;
a.MouseUp += MouseArea_MouseUp;
a.MouseLeave += MouseArea_MouseLeave;
// These two tend to obscure the other mouse events.
// You can uncomment them to see them in action.
// a.MouseMove += MouseArea_MouseMove;
// a.MouseHover += MouseArea_MouseHover;
a = (ImageAreaBase)imMap.Areas[2];
a.DrawImage += FocusArea_DrawImage;
a.Enter += FocusArea_Enter;
a.Leave += FocusArea_Leave;
}
