MessageBox C# Example

C# > Forms > MessageBox

Examples:

A. Displays a message box with specified text.

    MessageBox.Show("Text message");

B. Displays a message box with specified text, caption, and buttons.

string message = "Do you want to close this windows?";

string caption = "Question";

MessageBoxButtons buttons = MessageBoxButtons.YesNo;

DialogResult result = MessageBox.Show(message, caption, buttons);

if (result == System.Windows.Forms.DialogResult.Yes)

{

  this.Close();

}

AppActivate Visual Basic

VB.NET > Functions > AppActivate

Activates an application that is already running.

Example:
Start and activate notepad

AppActivate(Shell("C:\Windows\System32\notepad.exe", AppWinStyle.NormalFocus))

CurDir Visual Basic

VB.NET > Functions > CurDir 

Returns the current path.

Example:

MessageBox.Show(CurDir())

C# Random Color

C# > Color > Random

Random rnd = new Random();

Color randomColor = Color.FromArgb(rnd.Next(255), rnd.Next(255), rnd.Next(255));

Change DataGridView column to Hyperlink Runtime

C# > DataGridView > DataGridViewLinkCell

Example: Change DataGridView column to Hyperlink Runtime

foreach (DataGridViewRow r in dgv.Rows)

{

DataGridViewLinkCell lc = new DataGridViewLinkCell();

       lc.Value = r.Cells[1].Value;

       dgv[1, r.Index] = lc;

}

private void dgv_CellContentClick(object sender, DataGridViewCellEventArgs e)

{

if (e.RowIndex == -1)

              return;

if (dgv.Rows[e.RowIndex].Cells[e.ColumnIndex] is DataGridViewLinkCell)

       {

             string link = "http://www...";

             if(e.ColumnIndex == 1)

                System.Diagnostics.Process.Start(link  +                          dgv.Rows[e.RowIndex].Cells[4].Value as string);

       }

}

Read save data to Registry C# Example

C# > Win32 > RegistryKey 

RegistryKey represents a key-level node in the Windows registry

Example:

Save user name to registry

RegistryKey regKey = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("MyProgram");

if (regKey == null)

  regKey = Microsoft.Win32.Registry.CurrentUser.CreateSubKey("MyProgram");

if (regKey.GetValue("User", "") == null)

{

  regKey.SetValue("User", txtUser.Text);

}

else

{

  if (txtUser.Text != regKey.GetValue("User", "").ToString())

  {

    regKey.SetValue("User", txtUser.Text);

  }

}

regKey.Close();

Multiple Filter DataGridView DataSource

C# > DataGridView > Multiple Filter

RowFilter gets or sets the expression used to filter.

Example:

Filter by code or description

string rowFilter = string.Format("[{0}] like '%{1}%'", "Code", txtSearch.Text);

rowFilter += string.Format(" OR [{0}] like '%{1}%'", "Description", txtSearch.Text);

(DataGridView1.DataSource as DataTable).DefaultView.RowFilter = rowFilter;

Handle click event in Button Column in DataGridView

C# > DataGridView > DataGridViewButtonColumn

Add DataGridViewButtonColumn to your DataGridView.

To handle button click use CellClickEvent.

Example

private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)

{

  if (e.ColumnIndex == dataGridView1.Columns["Browse"].Index && e.RowIndex >= 0)

  {

               

  }

}

Call Statement VB.NET Example

VB.NET > Statements > Call

Call transfers control to a function or dynamic-link library.

Call keyword is used when the called expression doesn't start with an identifier.

Example:

Class mClass

    Public Sub Method()

        MessageBox.Show("Call statement")

    End Sub

End Class

Public Class Form1

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

        Call New mClass().Method()

    End Sub

End Class

HttpResponse ASP.NET

ASP.NET > System.Web > HttpResponse 

Encapsulates HTTP response information from an ASP.NET application.

• IsClientConnected

ASP.NET System.Web

ASP.NET > System.Web

System.Web contains classes and interfaces that enable browser-server communication.

• HttpResponse
• HttpCookie
• Web Controls

Rss Feed Reader Vb.net Example

VB.NET > XML > Rss Feed Reader






Example

 Dim url As String = "http://rss.cnn.com/rss/cnn_latest.rss"

        Dim rssFeed As HttpWebRequest = DirectCast(WebRequest.Create(url), HttpWebRequest)

        Dim response = rssFeed.GetResponse()

        Dim rssStream = response.GetResponseStream()

        Dim rssDoc As New XmlDocument()

        rssDoc.Load(rssStream)

        Dim rssItems As XmlNodeList = rssDoc.SelectNodes("rss/channel/item")

        Dim i As Integer = 0

        Dim dt As DataTable = New DataTable("table")

        dt.Columns.Add("title", Type.GetType("System.String"))

        dt.Columns.Add("link", Type.GetType("System.String"))

        While i < rssItems.Count

            Dim node As XmlNode = rssItems.Item(i).SelectSingleNode("title")

            Dim title As String

            Dim link As String

            If node IsNot Nothing Then

                title = node.InnerText

            Else

                title = ""

            End If

            node = rssItems.Item(i).SelectSingleNode("link")

            If node IsNot Nothing Then

                link = node.InnerText

            Else

                link = ""

            End If

            Dim dr As DataRow = dt.NewRow()

            dr("title") = title

            dr("link") = link

            dt.Rows.Add(dr)

            i += 1

        End While

        DataGridView1.DataSource = dt

#Region Directive Visual Basic Example

Visual Basic > Directives > #Region

Collapses and hides sections of code.

Example:

Public Class Form1

#Region "Person"

    Public Class Person

    End Class

#End Region

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    End Sub

End Class

Read XMLTYPE Oracle C#

C# > Oracle.DataAccess > Read XMLTYPE 

An OracleXmlType object represents an Oracle XMLType instance.

Example:

OracleConnection con = new OracleConnection() ;

con.ConnectionString = "Data Source=sid; User ID=xx; Password=xx; enlist=false; ";

con.Open();

OracleCommand xmlCmd = new OracleCommand();

xmlCmd.CommandText = "select xml from table ";

xmlCmd.Connection = con;

OracleDataReader poReader = xmlCmd.ExecuteReader();

OracleXmlType poXml;

while (poReader.Read())

{

     poXml = poReader.GetOracleXmlType(0);    

}

con.Close();

c# GuidAttribute Example

C# > InteropServices >  GuidAttribute 

Supplies an explicit Guid when an automatic GUID is undesirable.

When you write an application to be used as COM you have 
to give a unique name. In this case you need to apply GUID attribute.

Example

Class that is exported to COM with a fixed GUID

[GuidAttribute("bd2d60fa-8e40-4d06-ad6f-8760983efe33")]

public class ExposedToComClass

{

          

}