Currency Conversion Web Service with Asp .Net

I stumbled upon a excellent Currency Converter Web Service http://www.webservicex.net/CurrencyConvertor.asmx.

So thought of blogging on consuming a web service with Asp .Net.






















Start a new Asp .Net project and Add web reference to the above mentioned web service.

















Here is the code for invoking the ConversionRate method.

CurrencyConvertor.CurrencyConvertor cc = new CurrencyConvertor.CurrencyConvertor();
double dblConv;
protected void Page_Load(object sender, EventArgs e)
{

}
protected void btnUSDollar_Click(object sender, EventArgs e)
{
dblConv = cc.ConversionRate(CurrencyConvertor.Currency.USD,
CurrencyConvertor.Currency.INR);
lblConversion.Text = dblConv.ToString();
}
A few useful web services
http://webservices.oorsprong.org/websamples.countryinfo/CountryInfoService.wso
Related Blog
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News - Microsoft User Group meeting

http://www.hindu.com/2008/11/10/stories/2008111059460300.htm

AJAX .Net VIII : PasswordStrength Extender

PasswordStrength extender provides immediate feedback to the user about the strength of a password based on the site's Password Strength policy.

Add an Ajax Web Form or a classical Asp .Net Page and add a ScriptManager instead.
PasswordStrength extends a TextBox.
Add a TextBox and set the TextMode to Password. Add a PasswordStrength extender and set its TargetId to the TextBox.







HelpStatusLabelId Property
If you want extra information on the status of Password Strength you can use HelpStatusLabelId property.
Place a Label and set the HelpStatusLabelId Property of PasswordStrength extender control to the Label.







MinimumSymbolCharacters Property
The above example expects the user to enter 10 characters. But in many cases the site expects you to provide additional special characters, numeric characters and the like to make a strong password for this you can use properties like MinimumSymbolCharacters, MinimumLowerCaseCharacters, MinimumUpperCaseCharacters and MinimumNumericCharacters properties of PasswordStrength extender control.

In this example I am setting MinimumSymbolCharacters of PasswordStrength extender control to 1. As shown in the figure the user is expected to enter a special character to make it unbreakable.








PasswordStrength BarIndicator
We exploring TextIndicator option of PasswordStrength. It is possible to have BarIndicator for a PasswordStrength extender control.
You should have a CSS class for enabling BarIndicator as shown in the figure below.




















Now you can specify the CSS class in BarBorderCssClass property.

cc1:PasswordStrength ID="PasswordStrength1" runat="server"
StrengthIndicatorType="BarIndicator"
TargetControlID="txtPassword"
BarIndicatorCssClass = ""
BarBorderCssClass="BarBorder"

The user is expected to provide BarIndicatorCSSClass property also. To make things simple I am omitting the value.

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
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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();
}

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