如何从文件路径在邮件正文Outlook Sharepoint中显示图像

我需要从附加的图像中在邮件项目的正文中显示一个图像。但它一直显示文件名（img.jpg）。我尝试添加html标签，但它也显示了文件名。

如何让它显示图像而不是文件名？

这是我得到的：

   byte[] imageData = null;
        if (inspectorForm.txtEventPictureURL.Text != "")
          {
                //string imagepath = "http://---/Pictures/"+ inspectorForm.txtEventPictureURL.Text;
                //string imagepath = "C:'Users'---'img.jpg"; 
                string imagepath = inspectorForm.txtEventPictureURL.Text;
                //convert image url into byte
                //code here
                mailItem.Body = Environment.NewLine + "Event Title : " + inspectorForm.txtTitle.Text + Environment.NewLine + "Event Description : " + inspectorForm.txtDescription.Text + Environment.NewLine + "Event Start Date From :" + inspectorForm.dtpStartDate.Text + " To " + inspectorForm.dtpEndDate.Text + Environment.NewLine + "Time From : " + inspectorForm.cbStartHours.Text + " : " + inspectorForm.cbStartMins.Text + " To " + inspectorForm.cbEndHours.Text + " : " + inspectorForm.cbEndMins.Text + Environment.NewLine 
                            + "Image Url : " + Directory.GetDirectories(imagepath) ; 
          }