Contract.ForAll 方法

定義

命名空間:: System.Diagnostics.Contracts

組件:: mscorlib.dll, System.Diagnostics.Contracts.dll

組件:: netstandard.dll, System.Diagnostics.Contracts.dll

組件:: System.Diagnostics.Contracts.dll

組件:: mscorlib.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

多載

名稱	Description
ForAll(Int32, Int32, Predicate<Int32>)	判斷某一特定條件是否適用於指定範圍內的所有整數。
ForAll<T>(IEnumerable<T>, Predicate<T>)	判斷集合中的所有元素是否存在於函式中。

ForAll(Int32, Int32, Predicate<Int32>)

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

判斷某一特定條件是否適用於指定範圍內的所有整數。

public:
 static bool ForAll(int fromInclusive, int toExclusive, Predicate<int> ^ predicate);

public static bool ForAll(int fromInclusive, int toExclusive, Predicate<int> predicate);

static member ForAll : int * int * Predicate<int> -> bool

Public Shared Function ForAll (fromInclusive As Integer, toExclusive As Integer, predicate As Predicate(Of Integer)) As Boolean

參數

fromInclusive: Int32

第一個通過到 predicate的整數。

toExclusive: Int32

比最後一個經過 predicate的整數多一個。

predicate: Predicate<Int32>

用來評估指定範圍內整數的存在性。

傳回

Boolean

true如果predicate會對所有從 true 到 fromInclusive - 1 的整數回傳toExclusive。

例外狀況

ArgumentNullException

predicate 是 null。

ArgumentException

toExclusive 小於 fromInclusive。

範例

以下範例示範如何使用此 ForAll 方法判斷陣列是否有空元素。

using System;
using System.Diagnostics.Contracts;
using System.Collections.Generic;
namespace AssumeEx
{
    class Program
    {
        // Start application with at least two arguments
        static void Main(string[] args)
        {
            args[1] = null;
            Contract.Requires(args != null && Contract.ForAll(0, args.Length, i => args[i] != null));
            // test the ForAll method.  This is only for purpose of demonstrating how ForAll works.
            CheckIndexes(args);
            Stack<string> numbers = new Stack<string>();
            numbers.Push("one");
            numbers.Push("two");
            numbers.Push(null);
            numbers.Push("four");
            numbers.Push("five");
            Contract.Requires(numbers != null && !Contract.ForAll(numbers, (String x) => x != null));
            // test the ForAll generic overload.  This is only for purpose of demonstrating how ForAll works.
            CheckTypeArray(numbers);
        }

        private static bool CheckIndexes(string[] args)
        {
            try
            {
                if (args != null && !Contract.ForAll(0, args.Length, i => args[i] != null))
                    throw new ArgumentException("The parameter array has a null element", "args");
                return true;
            }
            catch (ArgumentException e)
            {
                Console.WriteLine(e.Message);
                return false;
            }
        }
        private static bool CheckTypeArray(IEnumerable<String> xs)
        {
            try
            {
                if (xs != null && !Contract.ForAll(xs, (String x) => x != null))
                    throw new ArgumentException("The parameter array has a null element", "indexes");
                return true;
            }
            catch (ArgumentException e)
            {
                Console.WriteLine(e.Message);
                return false;
            }
        }
    }
}

Imports System.Diagnostics.Contracts
Imports System.Collections.Generic


Class Program

    ' Start application with at least two arguments.
    Shared Sub Main(ByVal args() As String)
        args(1) = Nothing
        Contract.Requires(Not (args Is Nothing) AndAlso Contract.ForAll(args, Function(s) s Is Nothing))
        ' test the ForAll method.  This is only for purpose of demonstrating how ForAll works.
        CheckIndexes(args)
        Dim numbers As New Stack(Of String)
        numbers.Push("one")
        numbers.Push("two")
        numbers.Push("three")
        numbers.Push("four")
        numbers.Push("five")

        Contract.Requires(Not (numbers Is Nothing) AndAlso Not Contract.ForAll(numbers, Function(s) s Is Nothing))
        ' test the ForAll generic overload. This is only for purpose of demonstrating how ForAll works.
        CheckTypeArray(numbers)

    End Sub


    Private Shared Function CheckIndexes(ByVal args() As String) As Boolean
        Try
            If Not (args Is Nothing) AndAlso Not Contract.ForAll(0, args.Length, Function(i) args(i) Is Nothing) Then
                Throw New ArgumentException("The parameter array has a null element", "args")
            End If
            Return True
        Catch e As ArgumentException
            Console.WriteLine(e.Message)
            Return False
        End Try

    End Function 'CheckIndexes

    Private Shared Function CheckTypeArray(ByVal xs As Stack(Of String)) As Boolean

        Try
            If Not (xs Is Nothing) AndAlso Not Contract.ForAll(xs, Function(s) s Is Nothing) Then

                Throw New ArgumentException("The parameter array has a null element", "Stack")
            End If
            Return True

        Catch e As ArgumentException
            Console.WriteLine(e.Message)
            Return False
        End Try

    End Function 'CheckTypeArray
End Class

備註

toExclusive參數比最後一個整數多一個，以便利用從0開始的整數範圍長度。例如，整數 0 到 4 會設為 5。

另請參閱

TrueForAll(Predicate<T>)

適用於

ForAll<T>(IEnumerable<T>, Predicate<T>)

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

來源:: Contracts.cs

判斷集合中的所有元素是否存在於函式中。

public:
generic <typename T>
 static bool ForAll(System::Collections::Generic::IEnumerable<T> ^ collection, Predicate<T> ^ predicate);

public static bool ForAll<T>(System.Collections.Generic.IEnumerable<T> collection, Predicate<T> predicate);

static member ForAll : seq<'T> * Predicate<'T> -> bool

Public Shared Function ForAll(Of T) (collection As IEnumerable(Of T), predicate As Predicate(Of T)) As Boolean

類型參數

T

包含於 collection的型別。

參數

collection: IEnumerable<T>

將從中抽取型別 T 元素以傳遞給 predicate的集合。

predicate: Predicate<T>

評估所有元素 collection是否存在的函數。

傳回

Boolean

true當且僅當predicate對所有類型true為的元素回傳T。collection

例外狀況

ArgumentNullException

collection 或 predicate 為 null。

範例

以下範例示範如何使用此 ForAll 方法判斷集合是否有空元素。

using System;
using System.Diagnostics.Contracts;
using System.Collections.Generic;
namespace AssumeEx
{
    class Program
    {
        // Start application with at least two arguments
        static void Main(string[] args)
        {
            args[1] = null;
            Contract.Requires(args != null && Contract.ForAll(0, args.Length, i => args[i] != null));
            // test the ForAll method.  This is only for purpose of demonstrating how ForAll works.
            CheckIndexes(args);
            Stack<string> numbers = new Stack<string>();
            numbers.Push("one");
            numbers.Push("two");
            numbers.Push(null);
            numbers.Push("four");
            numbers.Push("five");
            Contract.Requires(numbers != null && !Contract.ForAll(numbers, (String x) => x != null));
            // test the ForAll generic overload.  This is only for purpose of demonstrating how ForAll works.
            CheckTypeArray(numbers);
        }

        private static bool CheckIndexes(string[] args)
        {
            try
            {
                if (args != null && !Contract.ForAll(0, args.Length, i => args[i] != null))
                    throw new ArgumentException("The parameter array has a null element", "args");
                return true;
            }
            catch (ArgumentException e)
            {
                Console.WriteLine(e.Message);
                return false;
            }
        }
        private static bool CheckTypeArray(IEnumerable<String> xs)
        {
            try
            {
                if (xs != null && !Contract.ForAll(xs, (String x) => x != null))
                    throw new ArgumentException("The parameter array has a null element", "indexes");
                return true;
            }
            catch (ArgumentException e)
            {
                Console.WriteLine(e.Message);
                return false;
            }
        }
    }
}

Imports System.Diagnostics.Contracts
Imports System.Collections.Generic


Class Program

    ' Start application with at least two arguments.
    Shared Sub Main(ByVal args() As String)
        args(1) = Nothing
        Contract.Requires(Not (args Is Nothing) AndAlso Contract.ForAll(args, Function(s) s Is Nothing))
        ' test the ForAll method.  This is only for purpose of demonstrating how ForAll works.
        CheckIndexes(args)
        Dim numbers As New Stack(Of String)
        numbers.Push("one")
        numbers.Push("two")
        numbers.Push("three")
        numbers.Push("four")
        numbers.Push("five")

        Contract.Requires(Not (numbers Is Nothing) AndAlso Not Contract.ForAll(numbers, Function(s) s Is Nothing))
        ' test the ForAll generic overload. This is only for purpose of demonstrating how ForAll works.
        CheckTypeArray(numbers)

    End Sub


    Private Shared Function CheckIndexes(ByVal args() As String) As Boolean
        Try
            If Not (args Is Nothing) AndAlso Not Contract.ForAll(0, args.Length, Function(i) args(i) Is Nothing) Then
                Throw New ArgumentException("The parameter array has a null element", "args")
            End If
            Return True
        Catch e As ArgumentException
            Console.WriteLine(e.Message)
            Return False
        End Try

    End Function 'CheckIndexes

    Private Shared Function CheckTypeArray(ByVal xs As Stack(Of String)) As Boolean

        Try
            If Not (xs Is Nothing) AndAlso Not Contract.ForAll(xs, Function(s) s Is Nothing) Then

                Throw New ArgumentException("The parameter array has a null element", "Stack")
            End If
            Return True

        Catch e As ArgumentException
            Console.WriteLine(e.Message)
            Return False
        End Try

    End Function 'CheckTypeArray
End Class

另請參閱

TrueForAll(Predicate<T>)

適用於

意見反應

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