1
當我使用SQL語句從SQL檢索varbinary數據並保存圖像/文件
SELECT File_Data
FROM Attachments
WHERE UserID = '12345' AND FileNames = 'testing1.jpg'
圖像下載和看上去很不錯。但是如果我放入存儲過程,它將在我的文件夾0123.中創建文件testing1.jpg
,但它不會在圖像中寫入數據,並且不會正確顯示。下面是我必須調用存儲過程並寫出來的內容。關於我在這裏做錯的任何想法?
出於測試目的:
- strfilename =
testing1.jpg
- 的userid =
12345
代碼:
protected void LoadFiles(string strfilename, int userid)
{
string fullname = strfilename;
using (SqlConnection cn = new SqlConnection(conn_string))
{
cn.Open();
using (SqlCommand cmd = new SqlCommand("GET_ATTACHMENT", cn))
{
cmd.CommandType = CommandType.StoredProcedure;
SqlParameter p1 = new SqlParameter("@FileName", SqlDbType.NVarChar, 255);
p1.Direction = ParameterDirection.Input;
p1.Value = strfilename;
cmd.Parameters.Add(p1);
SqlParameter p2 = new SqlParameter("@User_ID", SqlDbType.Int);
p2.Direction = ParameterDirection.Input;
p2.Value = userid;
cmd.Parameters.Add(p2);
// Tried using this statement but it did not work. //
SqlParameter pSub = new SqlParameter("@File_Data", SqlDbType.VarBinary);
pSub.Direction = ParameterDirection.ReturnValue;
cmd.Parameters.Add(pSub);
Response.Write(pSub);
// *** *** ///
using (SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.SequentialAccess))
{
if (dr.Read())
{
// For some reason the data being returned is blank
// When I run it in SQL I get data being returned.
byte[] fileData = (byte[])dr.GetValue(0);
using (System.IO.FileStream fs = new System.IO.FileStream("C:\\Testing\\" + (fullname), System.IO.FileMode.Create, System.IO.FileAccess.ReadWrite))
{
using (System.IO.BinaryWriter bw = new System.IO.BinaryWriter(fs))
{
bw.Write(fileData);
bw.Close();
}
}
}
dr.Close();
}
}
}
}
SQL Server存儲過程:
點ALTER PROCEDURE [dbo].[GET_ATTACHMENT]
@User_ID int,
@FileName nvarchar(250)
AS
BEGIN
SET NOCOUNT ON;
DECLARE @FileData varbinary(max)
Set @FileData = (SELECT File_Data FROM Attachments
WHERE UserID = @User_ID and
FileNames = @FileName);
SELECT @FileData
END
返回的數據是:System.Byte [] – mrmcg
返回的值爲空白。 – mrmcg
@mrmcg即使使用'CommandBehavior.Default'?你可以運行任何存儲過程嗎? –