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Tuple<T1, T2, T3, T4, T5, T6, T7, TRest>.Item4 Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's fourth component.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public ReadOnly Property Item4 As T4
public T4 Item4 { get; }

Property Value

Type: T4
The value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's fourth component.

Remarks

You can dynamically determine the type of the Item4 component in one of two ways:

Examples

The following example creates a 17-tuple object that contains population data for the city of Detroit, Michigan, from 1860 to 2000. The fourth component of the 17-tuple is the population in 1870. The example uses the Item4 property to display the population value and to calculate the annual rate of population change between 1870 and 1880.

Imports system.Windows.Media

Module Example
   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      outputBlock.FontFamily = new FontFamily("Courier New")

      Dim from1980 = Tuple.Create(1203339, 1027974, 951270)

      Dim from1910 As New Tuple(Of Integer, Integer, Integer, Integer, Integer, Integer, Integer,  _
          Tuple(Of Integer, Integer, Integer)) _
          (465766, 993078, 1568622, 1623452, 1849568, 1670144, 1511462, from1980)

      Dim population As New Tuple(Of String, Integer, Integer, Integer, Integer, Integer, Integer,  _
          Tuple(Of Integer, Integer, Integer, Integer, Integer, Integer, Integer, Tuple(Of Integer, Integer, Integer))) _
          ("Detroit", 1860, 45619, 79577, 116340, 205876, 285704, from1910)

      outputBlock.Text += String.Format("Population of {0}", population.Item1) & vbCrLf
      outputBlock.Text &= vbCrLf
      outputBlock.Text &= String.Format("{0,5}  {1,14}  {2,10}", "Year", "Population", "Change") & vbCrLf

      Dim year As Integer = population.Item2
      ShowPopulation(outputBlock, year, population.Item3)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Item4, population.Item3)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Item5, population.Item4)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Item6, population.Item5)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Item7, population.Item6)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item1, population.Item7)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item2, population.Rest.Item1)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item3, population.Rest.Item2)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item4, population.Rest.Item3)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item5, population.Rest.Item4)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item6, population.Rest.Item5)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Item7, population.Rest.Item6)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item1, population.Rest.Item7)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item2, population.Rest.Rest.Item1)
      year += 10
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item3, population.Rest.Rest.Item2)
   End Sub

   Private Sub ShowPopulationChange(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal year As Integer, ByVal newPopulation As Integer, ByVal oldPopulation As Integer)
        outputBlock.Text += String.Format("{0,5}  {1,14:N0}  {2,10:P2}", year, newPopulation, _
                          (newPopulation - oldPopulation) / oldPopulation / 10) & vbCrLf
   End Sub

   Private Sub ShowPopulation(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal year As Integer, ByVal newPopulation As Integer)
      outputBlock.Text += String.Format("{0,5}  {1,14:N0}  {2,10:P2}", year, newPopulation, "n/a") & vbCrLf
   End Sub
End Module
' The example displays the following output:
'
'    Population of Detroit
'    Year      Population      Change
'    1860          45,619         n/a
'    1870          79,577      7.44 %
'    1880         116,340      4.62 %
'    1890         205,876      7.70 %
'    1900         285,704      3.88 %
'    1910         465,766      6.30 %
'    1920         993,078     11.32 %
'    1930       1,568,622      5.80 %
'    1940       1,623,452      0.35 %
'    1950       1,849,568      1.39 %
'    1960       1,670,144     -0.97 %
'    1970       1,511,462     -0.95 %
'    1980       1,203,339     -2.04 %
'    1990       1,027,974     -1.46 %
'    2000         951,270     -0.75 %
using System;
using System.Windows.Media;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      outputBlock.FontFamily = new FontFamily("Courier New");

      Tuple<int, int, int> from1980 = Tuple.Create(1203339, 1027974, 951270);
      var from1910 = new Tuple<int, int, int, int, int, int, int, Tuple<int, int, int>>
          (465766, 993078, 1568622, 1623452, 1849568, 1670144, 1511462, from1980);
      var population = new Tuple<string, int, int, int, int, int, int,
          Tuple<int, int, int, int, int, int, int, Tuple<int, int, int>>>
          ("Detroit", 1860, 45619, 79577, 116340, 205876, 285704, from1910);

      outputBlock.Text += String.Format("Population of {0}\n\n", population.Item1);
      outputBlock.Text += String.Format("{0,5}  {1,14}  {2,10}\n", "Year", "Population", "Change");

      int year = population.Item2;
      ShowPopulation(outputBlock, year, population.Item3);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Item4, population.Item3);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Item5, population.Item4);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Item6, population.Item5);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Item7, population.Item6);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item1, population.Item7);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item2, population.Rest.Item1);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item3, population.Rest.Item2);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item4, population.Rest.Item3);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item5, population.Rest.Item4);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item6, population.Rest.Item5);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Item7, population.Rest.Item6);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item1, population.Rest.Item7);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item2, population.Rest.Rest.Item1);
      year += 10;
      ShowPopulationChange(outputBlock, year, population.Rest.Rest.Item3, population.Rest.Rest.Item2);
   }

   private static void ShowPopulationChange(System.Windows.Controls.TextBlock outputBlock, int year, int newPopulation, int oldPopulation)
   {
      outputBlock.Text += String.Format("{0,5}  {1,14:N0}  {2,10:P2}", year, newPopulation,
                        ((double)(newPopulation - oldPopulation) / oldPopulation) / 10) + "\n";
   }

   private static void ShowPopulation(System.Windows.Controls.TextBlock outputBlock, int year, int newPopulation)
   {
      outputBlock.Text += String.Format("{0,5}  {1,14:N0}  {2,10:P2}", year, newPopulation, "n/a") + "\n";
   }
}
// The example displays the following output:
//
//    Population of Detroit
//    Year      Population      Change
//    1860          45,619         n/a
//    1870          79,577      7.44 %
//    1880         116,340      4.62 %
//    1890         205,876      7.70 %
//    1900         285,704      3.88 %
//    1910         465,766      6.30 %
//    1920         993,078     11.32 %
//    1930       1,568,622      5.80 %
//    1940       1,623,452      0.35 %
//    1950       1,849,568      1.39 %
//    1960       1,670,144     -0.97 %
//    1970       1,511,462     -0.95 %
//    1980       1,203,339     -2.04 %
//    1990       1,027,974     -1.46 %
//    2000         951,270     -0.75 %

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.