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如何：讀取和寫入新建立的資料檔案

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System.IO.BinaryWriter 和 System.IO.BinaryReader 類別用於寫入和讀取資料，而不是字元字串。 下列範例顯示如何建立空的檔案資料流、將資料寫入其中，以及從中讀取資料。

此範例會在目前的目錄中建立一個稱為 Test.data 的資料檔案、建立相關聯的 BinaryWriter 和 BinaryReader 物件，而且會使用 BinaryWriter 物件，將 0 到 10 的整數寫入 Test.data，讓檔案指標留在檔案的結尾。 BinaryReader 物件接著會將檔案指標設定為原點， 並讀出指定的內容。

注意

如果 Test.data 已存在於目前的目錄中，則會擲回 IOException 例外狀況。 使用檔案模式選項 FileMode.Create，而不是 FileMode.CreateNew，來一律建立新檔案，而不會擲回例外狀況。

範例

using System;
using System.IO;

class MyStream
{
    private const string FILE_NAME = "Test.data";

    public static void Main()
    {
        if (File.Exists(FILE_NAME))
        {
            Console.WriteLine($"{FILE_NAME} already exists!");
            return;
        }

        using (FileStream fs = new FileStream(FILE_NAME, FileMode.CreateNew))
        {
            using (BinaryWriter w = new BinaryWriter(fs))
            {
                for (int i = 0; i < 11; i++)
                {
                    w.Write(i);
                }
            }
        }

        using (FileStream fs = new FileStream(FILE_NAME, FileMode.Open, FileAccess.Read))
        {
            using (BinaryReader r = new BinaryReader(fs))
            {
                for (int i = 0; i < 11; i++)
                {
                    Console.WriteLine(r.ReadInt32());
                }
            }
        }
    }
}


// The example creates a file named "Test.data" and writes the integers 0 through 10 to it in binary format.
// It then writes the contents of Test.data to the console with each integer on a separate line.

Imports System.IO

Class MyStream
    Private Const FILE_NAME As String = "Test.data"

    Public Shared Sub Main()
        If File.Exists(FILE_NAME) Then
            Console.WriteLine($"{FILE_NAME} already exists!")
            Return
        End If

        Using fs As New FileStream(FILE_NAME, FileMode.CreateNew)
            Using w As New BinaryWriter(fs)
                For i As Integer = 0 To 10
                    w.Write(i)
                Next
            End Using
        End Using

        Using fs As New FileStream(FILE_NAME, FileMode.Open, FileAccess.Read)
            Using r As New BinaryReader(fs)
                For i As Integer = 0 To 10
                    Console.WriteLine(r.ReadInt32())
                Next
            End Using
        End Using
    End Sub
End Class

' The example creates a file named "Test.data" and writes the integers 0 through 10 to it in binary format.
' It then writes the contents of Test.data to the console with each integer on a separate line.

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