Search This Blog

Thursday, January 30, 2014

LINQ DataTable compare date VB.NET

VB.NET > Data > DataTable > Filter with LINQ

LINQ DataTable compare date VB.NET example

   Dim dt As DataTable = New DataTable("table")
        dt.Columns.Add("id", Type.GetType("System.Int32"))
        dt.Columns.Add("name", Type.GetType("System.String"))
        dt.Columns.Add("date_of_birth", Type.GetType("System.DateTime"))
 

        Dim dr As DataRow = dt.NewRow()
        dr("id") = 1
        dr("name") = "john"
        dr("date_of_birth") = #1/1/2000#
        dt.Rows.Add(dr)

        dr = dt.NewRow()
        dr("id") = 2
        dr("name") = "dan"
        dr("date_of_birth") = #9/11/1973#
        dt.Rows.Add(dr)

        Dim filteredTable As DataTable = (From n In dt.AsEnumerable()
                            Where n.Field(Of Date)("date_of_birth") = #9/11/1973#
                    Select n).CopyToDataTable()




Wednesday, January 29, 2014

DateAdd VB.NET Example

VB.NET > Functions > DateAdd

DateAdd: add or subtract a specified time interval from a date.

Example:

Label1.Text = Date.Now
Label2.Text = DateAdd(DateInterval.Day, 1, Date.Now)
Label3.Text = DateAdd(DateInterval.Month, 1, Date.Now)
Label4.Text = DateAdd(DateInterval.Year, 1, Date.Now)




Tuesday, January 28, 2014

LINQ FirstOrDefault C# Example

C# > LINQ > FirstOrDefault

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

Example

string[] cars = { "audi", "ford", "mercedes", "dacia" };
string car = cars.FirstOrDefault(c => c == "ford"); //ford
car = cars.FirstOrDefault(c => c == "ford1"); //null


          
  



Single LINQ C# Example

C# > LINQ > Single

Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

Example

            string[] cars = { "audi", "ford", "mercedes", "dacia" };
            try
            {
                string car = cars.Single(c => c == "ford");
            }
            catch (System.InvalidOperationException)
            {
                MessageBox.Show ("Car not found!");
            }





Monday, January 27, 2014

How To Programmatically Change Printer Settings for Internet Explorer and WebBrowser Control in C#

C# > Forms >  WebBrowser > ShowPrintPreviewDialog

How To Programmatically Change Printer Settings for Internet Explorer and WebBrowser Control in C#

Example:

Change margin right property.





string strKey = "Software\\Microsoft\\Internet Explorer\\PageSetup";
bool boolWritable = true;
string strName = "margin_right";
object oValue = "0";
RegistryKey oKey = Registry.CurrentUser.OpenSubKey(strKey, boolWritable);
oKey.SetValue(strName, oValue);
oKey.Close();

webBrowser1.ShowPrintPreviewDialog();
 
 

ROW_NUMBER SQL Server Example

SQL Server > Built-in Functions >  ROW_NUMBER

Returns the sequential number of a row within a partition of a result set, starting at 1 for the first row in each partition.

Example:


CREATE TABLE #LocalTempTable(
       ID            int,
       Name   varchar(50),
       Salary int,
       DeptId int)

insert into #LocalTempTable(Id, Name, Salary, DeptId) values (1,'p1',100,1),  (2,'p2',200,1) ,  (3,'p2', 500,2)

SELECT ROW_NUMBER() OVER(ORDER BY Id DESC) AS Row,
    Name, Salary
FROM
       #LocalTempTable;

-- specify number of rows
WITH tbl AS
(
    SELECT Id, Name,
    ROW_NUMBER() OVER (ORDER BY Salary) AS RowNumber
    FROM #LocalTempTable
)

SELECT Id, Name, RowNumber 
FROM tbl
WHERE RowNumber BETWEEN 1 AND 2;

drop table #LocalTempTable










CapsLock pressed C# example

C# > Controls > > IsKeyLocked

IsKeyLocked check if CAPS LOCK, NUM LOCK, or SCROLL LOCK key is are pressed.

Example:

public static bool CapsLockActive()
{
     return Control.IsKeyLocked(Keys.CapsLock);
}