使用保存到内存流的图像导出文件

Question

我想将图像保存到已存储在内存流中的文件。

我已将asp.net图表保存到内存流中。

stream1 = new MemoryStream(); 
chart_location_3.SaveImage(stream1, ChartImageFormat.Png); 

然后我使用下面的代码导出为jpg。它触发保存提示，并创建文件，但图像将无法打开（“这不是一个有效的位图文件，或目前不支持其格式”）

System.Web.HttpResponse response = System.Web.HttpContext.Current.Response; 

System.Drawing.Image img; 

img = System.Drawing.Image.FromStream(stream1); 
response.ClearContent(); 
response.Clear(); 
Response.ContentType = "image/jpg"; 
response.AddHeader("Content-Disposition", "attachment; filename= Exported.jpg;"); 
response.Write(img); 
response.Flush(); 
response.End(); 

Answer 1

变化的响应写：

response.BinaryWrite(stream1.ToArray()); 

Answer 2

我用这样的事情之前：

http://www.dotnetperls.com/ashx

它生成图像浏览器在飞行中。希望能帮助到你。

---

根据dotnetperls的答案，它使用response.binarywrite。如下更改代码：

System.Web.HttpResponse response = System.Web.HttpContext.Current.Response; 

System.Drawing.Image img; 

img = System.Drawing.Image.FromStream(stream1); 
response.ClearContent(); 
response.Clear(); 
Response.ContentType = "image/jpg"; 
response.AddHeader("Content-Disposition", "attachment; filename= Exported.jpg;"); 
response.BinaryWrite(img); 
response.Flush(); 
response.End(); 

Answer 3

public HttpResponseMessage GetStatChart() 
    { 
     HttpResponseMessage response = new HttpResponseMessage(); 

     var chartImage = new Chart(600, 400); 
     chartImage.AddTitle("Chart Title"); 
     chartImage.AddSeries(
       name: "Employee", 
       chartType: "Pie", 
       axisLabel: "Name", 
       xValue: new[] { "Peter", "Andrew", "Julie", "Mary", "Dave" }, 
       yValues: new[] { "2", "6", "4", "5", "3" }); 
     byte[] chartBytes = chartImage.GetBytes(); 

     response.Content = new ByteArrayContent(chartBytes); 
     response.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg"); 

     return response; 



    }