在ASP.NET中创建水印的最佳方法是使用另一张图片来盖章。

Question

有人知道吗？想要能够动态地将一张图片用另一张图片作为水印，还可以批量处理。任何现有的库或您所知道的技术都可以。

- Ryan

Answer 1

这将回答你的问题：

http://www.codeproject.com/KB/GDI-plus/watermark.aspx

祝你好运！

- Ian P

Answer 2

我在使用ImageMagick时运气不错。它也有一个.NET API。

- Rich B

Answer 3

这是我的完整文章：http://forums.asp.net/p/1323176/2634923.aspx 请使用SDK命令提示符，导航到包含以下源代码的活动文件夹...然后使用编译代码。

vbc.exe watermark.vb /t:exe /out:watermark.exe

这将在文件夹中创建一个exe文件。该exe文件接受两个参数： 例如：

watermark.exe "c:\source folder" "c:\destination folder"

这将遍历父文件夹和所有子文件夹。找到的所有JPG图像都将使用您在代码中指定的图像添加水印，并复制到目标文件夹。原始图像将保持不变。

// watermark.vb --

Imports System
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Drawing.Imaging
Imports System.IO

Namespace WatermarkManager
    Class Watermark
        Shared sourceDirectory As String = "", destinationDirectory As String = ""

        Overloads Shared Sub Main(ByVal args() As String)

            'See if an argument was passed from the command line
            If args.Length = 2 Then
                sourceDirectory = args(0)
                destinationDirectory = args(1)

                ' make sure sourceFolder is legit
                If Directory.Exists(sourceDirectory) = False
                    TerminateExe("Invalid source folder. Folder does not exist.")
                    Exit Sub
                End If

                ' try and create destination folder
                Try
                    Directory.CreateDirectory(destinationDirectory)
                Catch
                    TerminateExe("Error creating destination folder. Invalid path cannot be created.")
                    Exit Sub
                End Try

                ' start the magic
                CreateHierarchy(sourceDirectory,destinationDirectory)

            ElseIf args.Length = 1
                If args(0) = "/?"
                    DisplayHelp()
                Else
                    TerminateExe("expected: watermark.exe [source path] [destination path]")
                End If
                Exit Sub
            Else
                TerminateExe("expected: watermark.exe [source path] [destination path]")
                Exit Sub
            End If

            TerminateExe()
        End Sub

        Shared Sub CreateHierarchy(ByVal sourceDirectory As String, ByVal destinationDirectory As String)

            Dim tmpSourceDirectory As String = sourceDirectory

            ' copy directory hierarchy to destination folder
            For Each Item As String In Directory.GetDirectories(sourceDirectory)
                Directory.CreateDirectory(destinationDirectory + Item.SubString(Item.LastIndexOf("\")))

                If hasSubDirectories(Item)
                    CreateSubDirectories(Item)
                End If
            Next

            ' reset destinationDirectory
            destinationDirectory = tmpSourceDirectory

            ' now that folder structure is set up, let's iterate through files
            For Each Item As String In Directory.GetDirectories(sourceDirectory)
                SearchDirectory(Item)
            Next
        End Sub

        Shared Function hasSubDirectories(ByVal path As String) As Boolean
            Dim subdirs() As String = Directory.GetDirectories(path)
            If subdirs.Length > 0
                Return True
            End If
            Return False
        End Function

        Shared Sub CheckFiles(ByVal path As String)
            For Each f As String In Directory.GetFiles(path)
                If f.SubString(f.Length-3).ToLower = "jpg"
                    WatermarkImage(f)
                End If
            Next
        End Sub

        Shared Sub WatermarkImage(ByVal f As String)

            Dim img As System.Drawing.Image = System.Drawing.Image.FromFile(f)
            Dim graphic As Graphics
            Dim indexedImage As New Bitmap(img)
            graphic = Graphics.FromImage(indexedImage)
            graphic.DrawImage(img, 0, 0, img.Width, img.Height)
            img = indexedImage

            graphic.SmoothingMode = SmoothingMode.AntiAlias
            graphic.InterpolationMode = InterpolationMode.HighQualityBicubic

            Dim x As Integer, y As Integer
            Dim source As New Bitmap("c:\watermark.png")
            Dim logo As New Bitmap(source, CInt(img.Width / 3), CInt(img.Width / 3))
            source.Dispose()
            x = img.Width - logo.Width
            y = img.Height - logo.Height
            graphic.DrawImage(logo, New Point(x,y))
            logo.Dispose()

            img.Save(destinationDirectory+f.SubString(f.LastIndexOf("\")), ImageFormat.Jpeg)
            indexedImage.Dispose()
            img.Dispose()
            graphic.Dispose()

            Console.WriteLine("successfully watermarked " + f.SubString(f.LastIndexOf("\")+1))
            Console.WriteLine("saved to: " + vbCrLf + destinationDirectory + vbCrLf)

        End Sub

        Shared Sub SearchDirectory(ByVal path As String)
            destinationDirectory = destinationDirectory + path.SubString(path.LastIndexOf("\"))
            CheckFiles(path)
            For Each Item As String In Directory.GetDirectories(path)
                destinationDirectory += Item.SubString(Item.LastIndexOf("\"))

                CheckFiles(Item)

                If hasSubDirectories(Item)
                    destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
                    SearchDirectory(Item)
                    destinationDirectory += Item.SubString(Item.LastIndexOf("\"))
                End If
                destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
            Next
            destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
        End Sub

        Shared Sub CreateSubDirectories(ByVal path As String)
            destinationDirectory = destinationDirectory + path.SubString(path.LastIndexOf("\"))
            For Each Item As String In Directory.GetDirectories(path)
                destinationDirectory += Item.SubString(Item.LastIndexOf("\"))
                Directory.CreateDirectory(destinationDirectory)
                Console.WriteLine(vbCrlf + "created: " + vbCrlf + destinationDirectory)

                If hasSubDirectories(Item)
                    destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
                    CreateSubDirectories(Item)
                    destinationDirectory += Item.SubString(Item.LastIndexOf("\"))
                End If
                destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
            Next
            destinationDirectory = destinationDirectory.SubString(0,destinationDirectory.LastIndexOf("\"))
        End Sub

        Shared Sub TerminateExe(ByVal Optional msg As String = "")
            If msg  ""
                Console.WriteLine(vbCrLf + "AN ERROR HAS OCCURRED //" + vbCrLf + msg)
            End If
            Console.WriteLine(vbCrLf + "Press [enter] to close...")
            'Console.Read()
        End Sub

        Shared Sub DisplayHelp()
            Console.WriteLine("watermark.exe accepts two parameters:" + vbCrLf + " - [source folder]")
            Console.WriteLine(" - [destination folder]")
            Console.WriteLine("ex." + vbCrLf + "watermark.exe ""c:\web_projects\dclr source"" ""d:\new_dclr\copy1 dest""")
            Console.WriteLine(vbCrLf + "Press [enter] to close...")
            Console.Read()
        End Sub
    End Class
End Namespace

- John West