ModuleMaster/handlers/getimage.ashx - main - ivan/ModMas

ModuleMaster/handlers/getimage.ashx
165 строк7 KB
i.krivokon
Initial commit
13 мар 2026, 13:49
13 мар 2026, 13:4900d9fb6
<%@ WebHandler Language="VB" Class="getFile" %>

Imports System.Data.SqlClient
Imports System.Drawing
Imports System.Drawing.Drawing2D

Public Class getFile : Implements IHttpHandler

    Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
        Dim rowid = context.Request.QueryString("id")
        Dim mode As String = IIf(IsNothing(context.Request.QueryString("mode")), "full", context.Request.QueryString("mode"))
        Dim message As New StringBuilder
        If IsNumeric(rowid) Then
            Dim storageName As String = context.Request.QueryString("storage")
            If IsNothing(storageName) Then
                storageName = "documents"
            End If
            Dim con As New SqlConnection(ConfigurationManager.ConnectionStrings("SERKIntranetConnectionString").ConnectionString)
            Dim com As New SqlCommand("", con)
            Dim sqlf As New sharedClasses.dbFunctions.SqlFunctions
            Dim noThumb As Boolean = False

            If mode = "thumb" Then
                noThumb = (sqlf.GetScalar("SELECT COUNT(*) FROM " & storageName & " WHERE [thumb] is not NULL and [id]=" & rowid) = "0")
                If noThumb Then
                    com.CommandText = "SELECT [doc], [name]  FROM " & storageName & " WHERE [id]=" & rowid
                Else
                    com.CommandText = "SELECT [thumb] as [doc], [name]  FROM " & storageName & " WHERE [id]=" & rowid
                End If
            Else
                com.CommandText = "SELECT parentid, [doc], [name]  FROM " & storageName & " WHERE [id]=" & rowid
            End If

            Dim img() As Byte = Nothing
            Dim fName As String = ""
            Dim fExtension As String = ""
            Dim parentID As String = ""
            Try
                con.Open()
                Dim r As SqlDataReader = com.ExecuteReader
                While r.Read
                    img = r.Item("doc")
                    fName = r.Item("name")
                    parentID = r.Item("parentid")
                End While
            Catch ex As Exception
            Finally
                If con.State <> Data.ConnectionState.Closed Then
                    con.Close()
                End If
            End Try

            Try
                If mode = "thumb" And noThumb Then
                    Using imgMemoryStream As New IO.MemoryStream(img)
                        Dim originalImage As Image = Image.FromStream(imgMemoryStream)
                        originalImage = ResizeImage(originalImage, New Size With {.Width = 320, .Height = 240})
                        Using stream As New System.IO.MemoryStream
                            originalImage.Save(stream, Imaging.ImageFormat.Jpeg)
                            img = stream.ToArray
                        End Using
                    End Using
                    SaveThumbToDb(storageName, rowid, img)
                ElseIf mode = "resize" Then
                    Using imgMemoryStream As New IO.MemoryStream(img)
                        Dim originalImage As Image = Image.FromStream(imgMemoryStream)

                        Dim owidth As Integer = originalImage.Width
                        Dim oheight As Integer = originalImage.Height

                        If originalImage.Width > 1920 Or originalImage.Height > 1080 Then
                            Try
                                originalImage = ResizeImage(originalImage, New Size With {.Width = 1920, .Height = 1080})

                                Using stream As New System.IO.MemoryStream
                                    originalImage.Save(stream, Imaging.ImageFormat.Jpeg)
                                    img = stream.ToArray
                                End Using
                                SaveThumbToDb(storageName, rowid, img, "resize")
                                message.AppendLine(rowid & " resized from " & owidth & "x" & oheight & " to 1920x1080 / " & lastError)
                            Catch ex As Exception
                                message.AppendLine("error (rowid " & rowid & " ): " & ex.Message)
                            End Try
                        Else
                            message.AppendLine("no resize " & owidth & "x" & oheight)
                        End If
                    End Using
                End If
            Catch ex As Exception
                context.Response.ContentType = "text/html"
                context.Response.Write("Error: " & ex.Message)
            End Try
            Try
                If mode = "thumb" Then
                    context.Response.ContentType = "image/jpeg"
                    context.Response.AppendHeader("Content-disposition", "attachment;filename=" & fName & ";")
                    context.Response.AppendHeader("Content-Length", img.Length.ToString())
                    context.Response.Cache.SetCacheability(HttpCacheability.Public)
                    context.Response.BufferOutput = False
                    context.Response.OutputStream.Write(img, 0, img.Length)
                ElseIf mode = "resize" Then
                    context.Response.ContentType = "text"
                    context.Response.Write(message)
                End If
            Catch ex As Exception

            End Try

        End If
    End Sub

    Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
        Get
            Return False
        End Get
    End Property

    Public Shared Function ResizeImage(ByVal image As Image,
      ByVal size As Size, Optional ByVal preserveAspectRatio As Boolean = True) As Image
        Dim newWidth As Integer
        Dim newHeight As Integer
        If preserveAspectRatio Then
            Dim originalWidth As Integer = image.Width
            Dim originalHeight As Integer = image.Height
            Dim percentWidth As Single = CSng(size.Width) / CSng(originalWidth)
            Dim percentHeight As Single = CSng(size.Height) / CSng(originalHeight)
            Dim percent As Single = If(percentHeight < percentWidth,
                    percentHeight, percentWidth)
            newWidth = CInt(originalWidth * percent)
            newHeight = CInt(originalHeight * percent)
        Else
            newWidth = size.Width
            newHeight = size.Height
        End If
        Dim newImage As Image = New Bitmap(newWidth, newHeight)
        Using graphicsHandle As Graphics = Graphics.FromImage(newImage)
            graphicsHandle.InterpolationMode = InterpolationMode.HighQualityBicubic
            graphicsHandle.DrawImage(image, 0, 0, newWidth, newHeight)
        End Using
        Return newImage
    End Function

    Dim lastError As String = ""

    Private Sub SaveThumbToDb(tablename As String, rowid As String, ByVal thumb() As Byte, Optional mode As String = "thumb")
        'Saving files to DB
        Dim sqlf As New sharedClasses.dbFunctions.SqlFunctions

        Dim com As New Data.SqlClient.SqlCommand
        If mode = "resize" Then
            com.CommandText = "UPDATE " & tablename & " SET doc = @thumb where id = @rowid "
        Else
            com.CommandText = "UPDATE " & tablename & " SET thumb = @thumb where id = @rowid "
        End If

        com.Parameters.Clear()
        With com.Parameters
            .AddWithValue("thumb", thumb)
            .AddWithValue("rowid", rowid)
        End With
        sqlf.NonQuery(com)
        lastError = sqlf.lastException
    End Sub

End Class