Tuple<T1,T2,T3,T4>.Item1 屬性

定義

命名空間:

System

組件:

System.Runtime.dll

組件:

mscorlib.dll

組件:

netstandard.dll

取得目前 Tuple<T1,T2,T3,T4> 物件之第一個元件的值。

public:
 property T1 Item1 { T1 get(); };

public T1 Item1 { get; }

member this.Item1 : 'T1

Public ReadOnly Property Item1 As T1

屬性值

T1

目前 Tuple<T1,T2,T3,T4> 物件之第一個元件的值。

範例

下列範例會定義 物件的陣列 Tuple<T1,T2,T3,T4> ，其元件包含城市的名稱、一年中的月份，以及該月份的平均高與低溫度。 然後，它會擷取並顯示每個元件的值。

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      Tuple<string, int, double, double>[] temperatures = 
            { Tuple.Create("New York, NY", 4, 61.0, 43.0),
              Tuple.Create("Chicago, IL", 2, 34.0, 18.0), 
              Tuple.Create("Newark, NJ", 4, 61.0, 43.0),
              Tuple.Create("Boston, MA", 6, 77.0, 59.0),
              Tuple.Create("Detroit, MI", 9, 74.0, 53.0),
              Tuple.Create("Minneapolis, MN", 8, 81.0, 61.0) }; 
      // Display the array of 4-tuple objects.
      Console.WriteLine("{0,41}", "Temperatures");
      Console.WriteLine("{0,-20} {1,5}    {2,4}  {3,4}\n", 
                        "City", "Month", "High", "Low");
      foreach (var temperature in temperatures)
         Console.WriteLine("{0,-20} {1,5}    {2,4:N1}  {3,4:N1}", 
                           temperature.Item1, 
                           DateTimeFormatInfo.CurrentInfo.GetAbbreviatedMonthName(temperature.Item2 - 1), 
                           temperature.Item3, temperature.Item4);
   }
}
// The example displays the following output:
//                                    Temperatures
//       City                 Month    High   Low
//       
//       New York, NY           Mar    61.0  43.0
//       Chicago, IL            Jan    34.0  18.0
//       Newark, NJ             Mar    61.0  43.0
//       Boston, MA             May    77.0  59.0
//       Detroit, MI            Aug    74.0  53.0
//       Minneapolis, MN        Jul    81.0  61.0

open System
open System.Globalization

let temperatures = 
    [| Tuple.Create("New York, NY", 4, 61.0, 43.0)
       Tuple.Create("Chicago, IL", 2, 34.0, 18.0) 
       Tuple.Create("Newark, NJ", 4, 61.0, 43.0)
       Tuple.Create("Boston, MA", 6, 77.0, 59.0)
       Tuple.Create("Detroit, MI", 9, 74.0, 53.0)
       Tuple.Create("Minneapolis, MN", 8, 81.0, 61.0) |] 

// Display the array of 4-tuple objects.
printfn "%41s" "Temperatures"
printfn "%-20s %5s    %4s  %4s\n" "City" "Month" "High" "Low"
for temperature in temperatures do
    printfn $"{temperature.Item1,-20} {DateTimeFormatInfo.CurrentInfo.GetAbbreviatedMonthName(temperature.Item2 - 1),5}    {temperature.Item3,4:N1}  {temperature.Item4,4:N1}" 
// The example displays the following output:
//                                    Temperatures
//       City                 Month    High   Low
//       
//       New York, NY           Mar    61.0  43.0
//       Chicago, IL            Jan    34.0  18.0
//       Newark, NJ             Mar    61.0  43.0
//       Boston, MA             May    77.0  59.0
//       Detroit, MI            Aug    74.0  53.0
//       Minneapolis, MN        Jul    81.0  61.0

Imports System.Globalization

Module Example
   Public Sub Main()
      Dim temperatures() = 
             { Tuple.Create("New York, NY", 4, 61, 43), _
               Tuple.Create("Chicago, IL", 2, 34, 18), _ 
               Tuple.Create("Newark, NJ", 4, 61, 43), _
               Tuple.Create("Boston, MA", 6, 77, 59), _
               Tuple.Create("Detroit, MI", 9, 74, 53), _
               Tuple.Create("Minneapolis, MN", 8, 81, 61) } 
      ' Display the array of 4-tuples.
      Console.WriteLine("{0,41}", "Temperatures")
      Console.WriteLine("{0,-20} {1,5}    {2,4}  {3,4}", 
                        "City", "Month", "High", "Low")
      Console.WriteLine()
      For Each temperature In temperatures
         Console.WriteLine("{0,-20} {1,5}    {2,4:N1}  {3,4:N1}", 
                           temperature.Item1, 
                           DateTimeFormatInfo.CurrentInfo.GetAbbreviatedMonthName(temperature.Item2 - 1), 
                           temperature.Item3, temperature.Item4)
      Next
   End Sub
End Module
' The example displays the following output:
'                                    Temperatures
'       City                 Month    High   Low
'       
'       New York, NY           Mar    61.0  43.0
'       Chicago, IL            Jan    34.0  18.0
'       Newark, NJ             Mar    61.0  43.0
'       Boston, MA             May    77.0  59.0
'       Detroit, MI            Aug    74.0  53.0
'       Minneapolis, MN        Jul    81.0  61.0

備註

您可以使用下列兩種方式之 Item1 一，動態判斷元件的類型：

• 藉由在 屬性所 Item1 傳回的值上呼叫 GetType 方法。

• 擷取 Type 代表 Tuple<T1,T2,T3,T4> 物件的 物件，並從其 Type.GetGenericArguments 方法傳回的陣列中擷取第一個專案。