我写了这个代码,但面对一个异常说:Parameter Not Valid.
检索从SQL Server图像
string connstr = @"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\db.mdf;Integrated Security=True;User Instance=True";
SqlConnection conn = new SqlConnection();
conn.ConnectionString = connstr;
conn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandText = "SELECT * FROM tbl";
SqlDataAdapter da = new SqlDataAdapter();
da.SelectCommand = cmd;
DataTable dt = new DataTable();
da.Fill(dt);
byte[] barrImg = (byte[])dt.Rows[1]["image"];
MemoryStream mstream = new MemoryStream();
mstream.Write(barrImg, 0, barrImg.Length);
mstream.Seek(0, SeekOrigin.Begin);
img.Image = Image.FromStream(mstream);
mstream.Close();
唯一的例外是:
在
Parameter is not valid.
Image.FromStream
线
码。
我检查了数据表分配给图像字段的值。它是System.Byte[]
。我追溯了代码。每件事似乎都是正确的。但它不起作用。
我搜索了这个问题。另一个网站首选设置mstream.Position = 0
。但那不行。
我用这段代码存储了我的图片。如果它可能是我保存了这个错误!
string connstr = @"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\db.mdf;Integrated Security=True;User Instance=True";
SqlConnection conn = new SqlConnection();
conn.ConnectionString = connstr;
conn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
string sql = "INSERT INTO tbl (name, family, image) VALUES ('name', 'family', '{0}')";
sql = string.Format(sql, Image.FromFile("test.jpg"));
cmd.CommandText = sql;
cmd.ExecuteNonQuery();
conn.Close();
新代码保存图像:
public byte[] ReadFile(string sPath)
{
byte[] data = null;
FileInfo fInfo = new FileInfo(sPath);
long numBytes = fInfo.Length;
FileStream fStream = new FileStream(sPath, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fStream);
data = br.ReadBytes((int)numBytes);
return data;
}
和:
private void cmdSave_Click(object sender, EventArgs e)
{
string connstr = @"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\db.mdf;Integrated Security=True;User Instance=True";
byte[] imageData = ReadFile("test.jpg");
SqlConnection CN = new SqlConnection(connstr);
string qry = "insert into tbl (name, family, image) VALUES ('name', 'family', '{0}')";
qry = string.Format(qry, imageData);
SqlCommand SqlCom = new SqlCommand(qry, CN);
CN.Open();
SqlCom.ExecuteNonQuery();
CN.Close();
}
我稍微改变了这个问题,以便它反映了当前面临的实际错误。之前提到的那个不是德国美人鱼。 – NotMe 2012-02-10 22:51:44
没有也许关于它...... – 2012-02-10 22:53:04
虽然我们在它,请张贴您的确切的错误信息。 – NotMe 2012-02-10 23:10:36