Question

c#怎么把二进制数据转换为图片

string ad = "疏楼龙宿";
string qry= @" SELECT 头像 FROM 注册表 WHERE 用户名= '"+ad+"' ";
ado a = new ado();
a.Connect();
Page.Response.Write(a.myCon.State + "<br/>");
a.myCom = new SqlCommand(qry, a.myCon);
SqlDataReader dr = a.myCom.ExecuteReader();

if (dr.Read())
{
byte[] bytes = (byte[])dr["Image"];
FileStream fs = new FileStream(Server.MapPath("//view//1.gif"), FileMode.Create, FileAccess.Write);
fs.Write(bytes, 0, bytes.Length);
fs.Flush();
fs.Close();
}
a.myCon.Close();

Image1.ImageUrl = "~/view/1.gif";
byte[] bytes = (byte[])dr["Image"]; 出错 这句话什么意思 那位前辈帮帮忙

Answer 1

请确认你的Image列是什么数据类型！
参考下面的代码：
public void GetImage()
{
SqlCommand cmd = new SqlCommand(@"SELECT name, photo FROM Temp", sqlConn);
sqlConn.Open();
SqlDataReader reader = cmd .ExecuteReader();
if (reader.Read())
{
image_filename= (string) reader.GetValue(0);
byte[] image_bytes = (byte[]) reader.GetValue(1);
MemoryStream ms = new MemoryStream(image_bytes);
Bitmap bmap = new Bitmap(ms);
return bmap;
}

追问

是image

Answer 2

byte[] byte_img = Convert.FromBase64String(img64);
if (byte_img.Length > 10 * 1024 * 1000)
{
      return ContentHelper.FailureInfo("图片大小超出限制");
}
MemoryStream s = new MemoryStream(byte_img);
Image image = Image.FromStream(s);