从图像数据类型DB中检索图像时参数无效

Question

This is my code; I try to retrieve image. I try to resolve but fail:

SqlCommand cmd = new SqlCommand("select pic from pic where idimg= '" + listBox1.Text + "'", con);
SqlDataReader r;

con.Open();
r = cmd.ExecuteReader();

while (r.Read())
{
    byte[] storedImage = (byte[])(r["pic"]);
    MemoryStream ms = new MemoryStream(storedImage);
    pictureBox1.Image = Image.FromStream(ms); // Error :Parameter is not valid
}

r.Close();
con.Close();

Answer 1

该参数无效，仅是show.while图像保存在db上而没有给定的周长，并且不会产生错误，从DB检索时发生错误