Themes in Asp .Net

Themes can be used to have a consistent look for User interface elements in Asp .Net.

Add a skin by selecting Skin from Add New Item dialog, give a good name, say Blue. This will create a folder called Blue inside App_Themes special folder.

A Skin File is used to set properties for Controls.




















Select the newly created Skin file. Inside that you can specify the control properties as shown in the figure below.









Here I have specified the Text Box to have light Yellow BackColor and Button to have Light Blue BackColor.



Now go back to the Asp .Net page and create the visual interface. Set the StyleSheetTheme property of document to the newly created SkinFile.











Now the controls will inherit the properties you have specified in the skin file.

Setting site wide theme in web.config
Instead of setting StyleSheetTheme property for individual forms go to web.config and identify the Page tag and set theme attribute to the newly created skin file.







Instead of directly tweaking the properties by going to properties windows, I used to place a control in the Asp .Net page set appropriate properties then navigate to the source and cut the control's tag and paste it in the skin file. While doing so ensure that you remove the id attribute.

Adding CSS File to Themes
It is possible to have a CSS file in themes folder. Select the themes folder and select Add New Item from WebSite menu. All files related to the current selection ie. themes will appear. Select Style Sheet.
















A style sheet can be used to specify html styles.








Here I am setting the background color of the form.

Related Blog
ASP.Net Master Page for Consistant look and feel for websites

WebParts in Asp .Net

Silverlight 3, WPF Positioning with ZIndex

You can use ZIndex property to change the order in which controls are rendered on a canvas.













The control with highest ZIndex value will be shown at the very top. Here Blue rectangle is having ZIndex 3, Yellow having ZIndex 2, so Blue rectanle will appear at the very top, followed by Yellow rectange and Cyan rectangle.

Programatically changing the ZIndex

private void Button_Click(object sender, RoutedEventArgs e)
{
Canvas.SetZIndex(rectCyan, 4);
}

Filling Windows Forms ListView with DataTable

If your are not familiar with List visit my blog Windows Forms ListView.

DataTable dt = new DataTable("Shalvin");
DataRow dr;
DataColumn dc;

private void Form1_Load(object sender, EventArgs e)
{
listView1.View = View.Details;

listView1.Columns.Add("Blog", 170);
listView1.Columns.Add("Author", 170);

dc = new DataColumn("Blog");
dt.Columns.Add(dc);

dc = new DataColumn("Author");
dt.Columns.Add(dc);

dr= dt.NewRow();
dr["Blog"] = "http://weblogs.asp.net/Scottgu/";
dr["Author"] = "Scott Guthrie";
dt.Rows.Add(dr);

dr = dt.NewRow();
dr["Blog"] = "DotNetShalvin.blogspot.com";
dr["Author"] = "Shalvin";
dt.Rows.Add(dr);

listView1.Items.Clear();







To make things simple I am creating a DataTable and DataRows by code .Afterward I am iterating through the DataRows collection and adding it into ListView's SubItems collection.


private void Form1_Load(object sender, EventArgs e)
{
..
..
ListViewItem lvbl = new ListViewItem("Add new record");
listView1.Items.Add(lvbl);
}

private void listView1_KeyPress(object sender, KeyPressEventArgs e)
{
if (listView1.FocusedItem.Text.ToString() == "Add new record")
MessageBox.Show("Add new record");
}

















VB .Net

Dim dt As New DataTable("Shalvin")
Dim dr As DataRow
Dim dc As DataColumn

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
ListView1.View = View.Details
ListView1.Columns.Add("Blog", 170)
ListView1.Columns.Add("Author", 170)

dc = New DataColumn("Blog")
dt.Columns.Add(dc)
dc = New DataColumn("Author")
dt.Columns.Add(dc)

dr = dt.NewRow()
dr("Blog") = "http://weblogs.asp.net/Scottgu/"
dr("Author") = "Scott Guthrie"
dt.Rows.Add(dr)

dr = dt.NewRow()
dr("Blog") = "DotNetShalvin.blogspot.com"
dr("Author") = "Shalvin"
dt.Rows.Add(dr)

For index As Integer = 0 To dt.Rows.Count - 1
Dim dr As DataRow = dt.Rows(index)
Dim lvi As New ListViewItem(dr("Blog").ToString())
ListView1.Items.Add(lvi)
lvi.SubItems.Add(dr("Author"))
Next


Related Blog :
DataTable DataColumn and DataRow (Asp .Net)
DataGridView - Extracting the Contents of Currently Selected Row

FileSystemWatcher Component and Class in WPF and Windows Forms

FileSystemWatcher Component (Class) can be used to monitor file system directories for changes. FileSystemWatcher Class in WPF FileSystemWatcher Class in found in System.IO namespace using System.IO is not added by default in WPF. using System.IO; private void Window_Loaded(object sender, RoutedEventArgs e) { FileSystemWatcher fsw = new FileSystemWatcher(); fsw.Path = @"c:\"; fsw.IncludeSubdirectories = true; fsw.EnableRaisingEvents = true; fsw.Created +=new FileSystemEventHandler(fsw_Created); } private void fsw_Created(object sender, FileSystemEventArgs e) { MessageBox.Show(e.FullPath + " created"); } FileSystemWatcher Component in Windows Forms Add a FileSystemWatcher to the form. Since it is a component it will appear in the component tray. Support if you want to monitor c: and its sub directories for changes, then set the Path property to C:, IncludeSubdirectories to True and EnableRaisingEvents to true. Now you can write event handlers for the FileSystemWatcher Component as follows: private void fileSystemWatcher1_Created(object sender, System.IO.FileSystemEventArgs e) { MessageBox.Show(e.FullPath + " created"); } private void fileSystemWatcher1_Deleted(object sender, System.IO.FileSystemEventArgs e) { MessageBox.Show(e.FullPath + " deleted"); } A better approach would be writing to an event log or a text file. Related blog: DataTable DataColumn and DataRow (Asp.Net)

LINQ to Sql

I am going to demonstrate LINQ to Sql by writing code.

Support you have a table called Categories in Shalvin database you need to first create a Entity. An Entity is a class that represents a Table or a view in the database.

Create a class as follows:
Set a reference to Data.Linq.

using System.Data.Linq.Mapping;

[Table]
public class Categories
{
[Column(IsPrimaryKey=true, IsDbGenerated=true)]
public int CategoryId { get; set; }

[Column]
public string CategoryName { get; set; }

[Column]
public string Description { get; set; }
}

Each property should have Column Atribute. I am also setting values of IsPrimaryKey and IsDbGenerated for CategoryId column. Editing is possible only if IsPrimaryKey is set to true. IsDbGenerated Indicated that it is an Identity column.


In the asp .net page :

using System.Data.Linq;
protected void Page_Load(object sender, EventArgs e)
{
string ConString = "Integrated Security=sspi;Initial Catalog=Shalvin";
DataContext db = new DataContext(ConString);
var tMovies = db.GetTable<categories>();
GridView1.DataSource = tMovies;
DataBind();
}Now suppose you are interested only in viewing the Categories table with CategoryName 'Confections'.

GridView1.DataSource = tMovies.Where(m => m.CategoryName.Contains("Beverages"));The DataContext is the source of all entities mapped over a database connection. It tracks changes that you made to all retrieved entities .

Linq to Sql with Visual Studio Tools

Having seen the internals lets turn our attention to the Visual Studio Support of Linq to Sql.
Here I have started an Empty Visual Studio Project and Added a Linq to Sql Classes from the Add New Item Dialog. I have renamed it AirLines.dbml

On to the design surface it is possible to drag the table from Database Explorer.

That's all I have to do and I am ready to do CRUD operation with the selected tables.

AirLinesDataContext context = new AirLinesDataContext();
protected void Page_Load(object sender, EventArgs e)
{
  if (!IsPostBack)
  {
    GridView1.DataSource = context.Locations;

    DropDownList1.DataSource = context.Locations;
    DropDownList1.DataTextField = "LocationName";
    DropDownList1.DataValueField = "LocationId";

    DataBind();
  }
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
  Response.Write(DropDownList1.SelectedValue.ToString());
}

protected void btnInsertLocation_Click(object sender, EventArgs e)
{
  var loc = new Location { LocationName = "London", Latitude =67 };
  context.Locations.InsertOnSubmit(loc);
  context.SubmitChanges();
}

Related Blogs
Linq to Objects
Linq to Xml (Code Snippets)

Microsoft Innovation Days Kochi

Learn for free about building reliable, high performance applications with a super-rich user interactivity using Microsoft technologies, such as the Visual Studio 2008, SQL Server 2008, Windows Server 2008, Silverlight 2 RC0 and Internet Explorer 8.

Date: November 6, 2008 (Thursday)

Venue: Taj Residency
Marine Drive, Shanmugham Road
Ernakulam, Cochin 682304

9 am Tea and Registration

9:45 AM Keynote - The magic of Software
Sneak peak into the host of technology innovations that Microsoft is working on - Windows 7, Live platform, Cloud services and many more , accompanied with uber-cool demos.

10:45 AM Next generation web experience with IE 8 and Silverlight
Learn how you can leverage some of the developer features in IE 8 to "light up" your web site and provide a compelling experience to your website users by rendering your data on Silverlight controls.

12:00 PM SQL Server – Optimize your Queries

Lunch Break (1.30 - 2.30)

2:30 PM Partnering with Microsoft
Learn about the various partnering opportunities with Microsoft that will support and enhance your development and marketing efforts.

3:00 PM AJAX - Get it right for your ASP.NET Applications
Find out how to AJAX Enabling your ASP.NET Applications in the right way and also explore some of the best practices to build a high performance web application. Finally, learn how the new version of ASP.NET improves AJAX enabled web development.

4:30 PM The developer's toolkit for building .Net applications.
Find out the host of tools you can use to analyze and identify performance bottlenecks in your .Net applications. Explores some of the in-built tools that ships with the .NET SDK such as ildasm, gacutil, ngen, fxcop etc and and features in Visual Studio. which will help you develop better, faster, more secure, error free NET applications.

Click here to register

Silverlight 3/Wpf : Adding Controls Dynamicallys

Lets see how to dynamically add controls and attaching event handler to the added control.

Here I am creating an object of button class and adding it into the Grid using the Add method of Grid's Children property.

private void btnAddControl_Click(object sender, RoutedEventArgs e)
{
Button btn = new Button();
btn.Click += new RoutedEventHandler(btn_Click);
btn.Content = "Shalvin";
btn.Width = 75;
btn.Height = 25;
Grid1.Children.Add(btn);
}

private void btn_Click(object sender, RoutedEventArgs e)
{
//MessageBox works only with WPF , Silverlight 3 and not with Silverlight 2
MessageBox.Show("ShalvinPD.blogspot.com");
}

Result

WPF Routed Event

A routed event is a type of event that can invoke handlers on multiple listeners in an element tree, rather than just on the object that raised the event.

For example if you want a single event handler for the buttons inside a Grid you can define a Routed event as Button.Click = "Grid_Click" inside the Grid as shown in the diagram.









private void Grid_Click(object sender, RoutedEventArgs e)
{
//MessageBox works only with WPF and not Silverlight 2
MessageBox.Show("ShalvinPD.blogspot.com");
}