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Wie speichert man Bilder in einer varbinary(max)-Spalte?

Verwenden Sie dies, um die Datei in ein Byte-Array einzulesen:

    // Old fashioned way
    public static byte[] ReadFile(string filePath)
    {
        byte[] buffer;
        FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
        try
        {
            int length = (int)fileStream.Length;  // get file length
            buffer = new byte[length];            // create buffer
            int count;                            // actual number of bytes read
            int sum = 0;                          // total number of bytes read

            // read until Read method returns 0 (end of the stream has been reached)
            while ((count = fileStream.Read(buffer, sum, length - sum)) > 0)
                sum += count;  // sum is a buffer offset for next reading
        }
        finally
        {
            fileStream.Close();
        }
        return buffer;
    }

oder

    // Thanks Magnus!
    byte[] data = System.IO.File.ReadAllBytes(filePath);

Speichern Sie dann die Bilddaten mit diesem (ich verwende eine Bildklasse "Instanz", die meine Bildinformationen und mein Byte-Array in instance.Data enthält):

   using(SqlCommand cm = new SqlCommand("SaveImage", connection, transaction)){
       cm.CommandType = CommandType.StoredProcedure;
       cm.Parameters.Add(new SqlParameter("@Id", SqlDbType.Int,0, ParameterDirection.InputOutput, false, 10, 0, "Id", DataRowVersion.Current, (SqlInt32)instance.Id));
       cm.Parameters.Add(new SqlParameter("@Title", SqlDbType.NVarChar,50, ParameterDirection.Input, false, 0, 0, "Title", DataRowVersion.Current, (SqlString)instance.Title));
       if (instance.Data.Length > 0)
       {
           cm.Parameters.Add(new SqlParameter("@Data", SqlDbType.VarBinary,instance.Data.Length, ParameterDirection.Input, false, 0, 0, "Data", DataRowVersion.Current, (SqlBinary)instance.Data));
       }
       else
       {
           cm.Parameters.Add(new SqlParameter("@Data", SqlDbType.VarBinary,0, ParameterDirection.Input, false, 0, 0, "Data", DataRowVersion.Current, DBNull.Value));                    
       }

       cm.ExecuteNonQuery();
   )

Und hier ist ein Beispiel für eine gespeicherte Prozedur:

CREATE PROCEDURE SaveImage
(
@Id int OUTPUT 
,@Title nvarchar(50)
,@Data varbinary(MAX)
)
AS
SET NOCOUNT ON
SET XACT_ABORT ON

IF @Id IS NULL OR @Id <= 0
BEGIN
SELECT @Id = ISNULL(MAX([Id]),0) + 1 FROM [dbo].[Images]
END

INSERT INTO [dbo].[Images] (
[Id]
,[Title]
,[Data]
) VALUES (
@Id
,@Title
,@Data
)