VB.NET LINQ TO SQL Delete Rows From Database

ADO.NET > LINQ TO SQL > Delete rows from database

DeleteOnSubmit removes entity, but does not disappear from the query results until after SubmitChanges is called. 

Example


C#

var deleteData =
    from details in db.GetDetails
    where details.ID == 1
    select details;

foreach (var detail in deleteData )
{
    db.Details.DeleteOnSubmit(detail);
}

try
{
    db.SubmitChanges();
}
catch (Exception e)
{
}

VB.Net

Dim deleteData = _

    From details In db.GetDetails() _

    Where details.ID = 1 _

    Select details

For Each detail As Detail In deleteData

    db.Details.DeleteOnSubmit(detail)

Next 

Try

    db.SubmitChanges()

Catch ex As Exception

End Try

Check Deny Access File C#

C# > System.Security > AccessControl > AuthorizationRuleCollection 

AuthorizationRuleCollection 

Represents a collection of AuthorizationRule objects.

Example

Check Deny Access File C#

public bool CheckDenyAccessFile(string filePath)

{

       FileSecurity fs = File.GetAccessControl(filePath);

       AuthorizationRuleCollection acl = fs.GetAccessRules(true, true, typeof(System.Security.Principal.SecurityIdentifier));

       bool deny = false;

       for (int x = 0; x < acl.Count; x++)

       {

              FileSystemAccessRule currentRule = (FileSystemAccessRule)acl[x];

              AccessControlType accessType = currentRule.AccessControlType;

              if (accessType == AccessControlType.Deny && (currentRule.FileSystemRights & FileSystemRights.ListDirectory) == FileSystemRights.ListDirectory)

                {

                    deny = true;

                    break;

                }

        }

        return deny;

}

Writes lines to text file C#

C# > IO  > FileInfo > CreateText

Writes text a new text file.

Example

Writes lines to text file C#

string path = Path.GetTempFileName();

FileInfo fi = new FileInfo(path);

using (StreamWriter sw = fi.CreateText())

{

      sw.WriteLine("Line1");

      sw.WriteLine("Line2");

      sw.WriteLine("Line3");

      sw.WriteLine("Line4");

}      

FileInfo Class C#

C# > IO  > FileInfo Class

FileInfo

Use this class for working with files: create, open, delete, 

move, rename.

Methods

• CreateText

Properties

• Length

String IsNullOrEmpty C# Example

C# > String > Methods > IsNullOrEmpty

With this method you can test simultaneously test whether a String is null or its value is Empty.

Example

string s = "test";

bool b = String.IsNullOrEmpty(s); // false

           

s = null;

b = String.IsNullOrEmpty(s); // true

           

s = "";

b = String.IsNullOrEmpty(s); // true

s = " ";

b = String.IsNullOrEmpty(s); // false

CONVERT SQL Server Example

SQL Server > Built-in Functions > CONVERT

CONVERT converts an expression of one data type to another.

Example

select CONVERT(nvarchar(30), GETDATE(), 100)

result

Oct 15 2014  9:54AM

Other examples:

How to format date and time

Where keyword generic generic type constraint example C#

C# > Generics > where - generic type constraint

With where keyword you can apply restrictions to the kinds of types that client code can use for type arguments when it instantiates the generics class.

Example

    public class A

    {

    }

    public class B:A

    {

    }

    public class GenericList <T> where T : A

    {

    }

    GenericList<A> lst1 = new GenericList<A>(); // OK

    GenericList<B> lst2 = new GenericList<B>(); // OK B derives from A

    GenericList<int> lst3 = new GenericList<int>(); //Error  1      The type 'int' cannot be used as type parameter 'T' in the generic type or method 'WindowsFormsApplication1.GenericList'. There is no boxing conversion from 'int' to 'WindowsFormsApplication1.A'.

       

Ushort Type C# Example

C# > Types > ushort

The ushort keyword is an integral type.
Range: 0 to 63535


Example:

byte k = 63535; // ok

k = 63536;      // Error   

Byte Type C# Example

C# > Types > byte

The byte keyword is an integral type.
Range: 0 to 255


Example:

byte k = 255; // ok

k = 256;      // Error   

APP_NAME SQL Server Example

SQL Server > Built-in Functions > APP_NAME

APP_NAME returns the application name for the current session.

Example:

select APP_NAME();

Result:

Microsoft SQL Server Data Tools, T-SQL Editor

Create form in runtime C#

C# > Windows > Form

A Form is a representation of any window displayed in your application.

Properties

• KeyPreview

Example

Create form in runtime

Form form1 = new Form();

Button button1 = new Button();

button1.Text = "OK";

button1.Location = new Point(5, 5);

form1.Text = "My Form";

form1.FormBorderStyle = FormBorderStyle.FixedDialog;

form1.MaximizeBox = false;

form1.MinimizeBox = false;

form1.StartPosition = FormStartPosition.CenterScreen;

form1.Controls.Add(button1);

form1.ShowDialog();

Jenkins Email Error: Network is unreachable

Jenkins > Email > Network is unreachable error

send failed, exception: javax.mail.MessagingException: Could not connect to SMTP host:     , port: 25;
nested exception is:  java.net.SocketException: Network is unreachable: connect

Solution:

The problem is because java 1.7 uses IPv6 by default.
To fix this add Java Option from command line:

setx _JAVA_OPTIONS -Djava.net.preferIPv4Stack=true**

Set Next Build Number Jenkins

Jenkins > Next Build Number

Install plugin Next Build Number

https://wiki.jenkins-ci.org/display/JENKINS/Next+Build+Number+Plugin

After install you have to reload configuration from disk

Go to configure project and click on Set Next Build Number

ProcessStartInfo Example - Start Microsoft Word

C# > Diagnostics > ProcessStartInfo

ProcessStartInfo specifies a set of values that are used when you start a process.

Example 

Start word

ProcessStartInfo startInfo = new ProcessStartInfo();

startInfo.FileName = "WINWORD.EXE";

Process.Start(startInfo);

Process Class C#

C# > Diagnostics > Process Class

A process is a running application.
Process class provide access to a process that is running on a computer. 
The Process component is a useful tool for starting, stopping, controlling, and monitoring apps.

Methods:

• Start

System.Diagnostics Namespace C#

C# > System.Diagnostics

System.Diagnostics contains classes that allow to interact with 

• system processes
• event logs
• performance counters

Classes

• Process
• ProcessStartInfo
• StopWatch

SqlClient namespace

C# > System.Data  > SqlClient

SqlClient namespace is the.NET Framework Data Provider for SQL Server.

• SqlBulkCopy

SqlBulkCopy C# SQL Server import data example

C# > System.Data  > SqlClient > SqlBulkCopy

SqlBulkCopy efficiently bulk load a SQL Server table with data from another source.
The data source is not limited to SQL Server, any data source can be used.
SqlBulkCopy offers a significant performance.






Example:

string sourceConnectionString = "YourSourceConnectionString";

string destinationConnectionString = "YourDestinationConnectionString";

using (SqlConnection sourceConnection =

       new SqlConnection(sourceConnectionString))

            {

                sourceConnection.Open();

                SqlCommand commandSourceData = new SqlCommand(

                    "SELECT * FROM source_table;", sourceConnection);

                SqlDataReader reader = commandSourceData.ExecuteReader();

                using (SqlConnection destinationConnection =

                           new SqlConnection(destinationConnectionString))

                {

                    destinationConnection.Open();

                    using (SqlBulkCopy bulkCopy =

                               new SqlBulkCopy(destinationConnection))

                    {

                        bulkCopy.DestinationTableName = "dbo.destination_table";

                        try

                        {

                            bulkCopy.WriteToServer(reader);

                        }

                        catch (Exception ex)

                        {

                            MessageBox.Show(ex.Message);

                        }

                        finally

                        {

                            reader.Close();

                        }

                    }

                }

            }

GetDrives C# Example

C# > Files > DriverInfo > GetDrives 

Retrieves the drive names of all logical drives

Example:
DriveInfo[] allDrives = DriveInfo.GetDrives();

foreach (DriveInfo d in allDrives)

{

   tvLeft.Nodes.Add(d.Name);  

}

RichTextBox control insert color text

C# > RichTextBox Control > SelectionColor 

Gets or sets the text color of the current text selection or insertion point.

Example

private void AppendText(RichTextBox rtb, string text, Color color)

{

       rtb.SelectionStart = rtb.TextLength;

       rtb.SelectionLength = 0;

       rtb.SelectionColor = color;

       rtb.AppendText(text);

       rtb.SelectionColor = rtb.ForeColor;

}

AppendText(richTextBox1, "Blue", Color.Blue);

AppendText(richTextBox1, "Red", Color.Red);   

Telerik RadGridView clear all rows

Telerik > RadGridView > Rows > Clear

Clear  is a efficient solution to remove all rows since the grid's events will be suspended.

Example

this.radGridView1.Rows.Clear();

Bach file Current Directory Example

Bach file > Current directory 

set CURRENT_DIR=%CD%
cd ..\..\install\kits
install.bat
cd %CURRENT_DIR%

Configure Jenkins to use Mercurial

Jenkins > Mercurial 

Mercurial Plugin: Install the Jenkins Mercurial Plugin first (read more https://wiki.jenkins-ci.org/display/JENKINS/Mercurial+Plugin)

Source Code Management: Configure for Mercurial

Reduce unnecessary builds by specifying a comma or space delimited list of "modules" within the repository. A module is a directory name within the repository that this project lives.

To do that press advanced button:

This will detect changes only in sdks subdirectory in src directory:

Environment UserName property C# example

C#  > System > Environment Class > UserName

UserName is used to identify the user on the current thread, the user name of the person who is logged on to Windows.

Example

  string user = Environment.UserName;