c# - 如何将图像 url 转换为 system.drawing.image

Question

我正在使用 VB.Net 我有一个图像的 url，比方说 http://localhost/image.gif

我需要从该文件创建一个 System.Drawing.Image 对象。

注意将其保存到文件然后打开它不是我的选择之一我也在使用 ItextSharp

这是我的代码:

Dim rect As iTextSharp.text.Rectangle
        rect = iTextSharp.text.PageSize.LETTER
        Dim x As PDFDocument = New PDFDocument("chart", rect, 1, 1, 1, 1)

        x.UserName = objCurrentUser.FullName
        x.WritePageHeader(1)
        For i = 0 To chartObj.Count - 1
            Dim chartLink as string = "http://localhost/image.gif"
            x.writechart( ** it only accept system.darwing.image ** ) 

        Next

        x.WritePageFooter()
        x.Finish(False)

Answer 1

您可以使用 WebClient 类下载图像，然后使用 MemoryStream 读取它:

C#

WebClient wc = new WebClient();
byte[] bytes = wc.DownloadData("http://localhost/image.gif");
MemoryStream ms = new MemoryStream(bytes);
System.Drawing.Image img = System.Drawing.Image.FromStream(ms);

VB

Dim wc As New WebClient()
Dim bytes As Byte() = wc.DownloadData("http://localhost/image.gif")
Dim ms As New MemoryStream(bytes)
Dim img As System.Drawing.Image = System.Drawing.Image.FromStream(ms)