获取 [C#] SqlConnection pubsConn = new SqlConnection("Data Source=localhost;Integrated Security=SSPI;Initial Catalog=pubs;"); SqlCommand logoCMD = new SqlCommand("SELECT pub_id, logo FROM pub_info", pubsConn);FileStream fs; // Writes the BLOB to a file (*.bmp). BinaryWriter bw; // Streams the BLOB to the FileStream object.int bufferSize = 100; // Size of the BLOB buffer. byte[] outbyte = new byte[bufferSize]; // The BLOB byte[] buffer to be filled by GetBytes. long retval; // The bytes returned from GetBytes. long startIndex = 0; // The starting position in the BLOB output.string pub_id = ""; // The publisher id to use in the file name.// Open the connection and read data into the DataReader. pubsConn.Open(); SqlDataReader myReader = logoCMD.ExecuteReader(CommandBehavior.SequentialAccess);while (myReader.Read()) { // Get the publisher id, which must occur before getting the logo. pub_id = myReader.GetString(0); // Create a file to hold the output. fs = new FileStream("logo" + pub_id + ".bmp", FileMode.OpenOrCreate, FileAccess.Write); bw = new BinaryWriter(fs); // Reset the starting byte for the new BLOB. startIndex = 0; // Read the bytes into outbyte[] and retain the number of bytes returned. retval = myReader.GetBytes(1, startIndex, outbyte, 0, bufferSize); // Continue reading and writing while there are bytes beyond the size of the buffer. while (retval == bufferSize) { bw.Write(outbyte); bw.Flush(); // Reposition the start index to the end of the last buffer and fill the buffer. startIndex += bufferSize; retval = myReader.GetBytes(1, startIndex, outbyte, 0, bufferSize); } // Write the remaining buffer. bw.Write(outbyte, 0, (int)retval - 1); bw.Flush(); // Close the output file. bw.Close(); fs.Close(); }// Close the reader and the connection. myReader.Close(); pubsConn.Close();
[C#]
SqlConnection pubsConn = new SqlConnection("Data Source=localhost;Integrated Security=SSPI;Initial Catalog=pubs;");
SqlCommand logoCMD = new SqlCommand("SELECT pub_id, logo FROM pub_info", pubsConn);FileStream fs; // Writes the BLOB to a file (*.bmp).
BinaryWriter bw; // Streams the BLOB to the FileStream object.int bufferSize = 100; // Size of the BLOB buffer.
byte[] outbyte = new byte[bufferSize]; // The BLOB byte[] buffer to be filled by GetBytes.
long retval; // The bytes returned from GetBytes.
long startIndex = 0; // The starting position in the BLOB output.string pub_id = ""; // The publisher id to use in the file name.// Open the connection and read data into the DataReader.
pubsConn.Open();
SqlDataReader myReader = logoCMD.ExecuteReader(CommandBehavior.SequentialAccess);while (myReader.Read())
{
// Get the publisher id, which must occur before getting the logo.
pub_id = myReader.GetString(0); // Create a file to hold the output.
fs = new FileStream("logo" + pub_id + ".bmp", FileMode.OpenOrCreate, FileAccess.Write);
bw = new BinaryWriter(fs); // Reset the starting byte for the new BLOB.
startIndex = 0; // Read the bytes into outbyte[] and retain the number of bytes returned.
retval = myReader.GetBytes(1, startIndex, outbyte, 0, bufferSize); // Continue reading and writing while there are bytes beyond the size of the buffer.
while (retval == bufferSize)
{
bw.Write(outbyte);
bw.Flush(); // Reposition the start index to the end of the last buffer and fill the buffer.
startIndex += bufferSize;
retval = myReader.GetBytes(1, startIndex, outbyte, 0, bufferSize);
} // Write the remaining buffer.
bw.Write(outbyte, 0, (int)retval - 1);
bw.Flush(); // Close the output file.
bw.Close();
fs.Close();
}// Close the reader and the connection.
myReader.Close();
pubsConn.Close();
[C#]
using System;
using System.Data;
using System.Data.SqlClient;
using System.IO;public class EmployeeData
{
public static void Main()
{
DateTime hireDate = DateTime.Parse("5/21/99");
AddEmployee("Jones", "Mary", "Sales Representative", hireDate, 5, "jones.bmp");
} public static void AddEmployee(string lastName, string firstName, string title, DateTime hireDate , int reportsTo, string photoFilePath)
{
byte[] photo = GetPhoto(photoFilePath); SqlConnection nwindConn = new SqlConnection("Data Source=localhost;Integrated Security=SSPI;Initial Catalog=Northwind;"); SqlCommand addEmp = new SqlCommand("INSERT INTO Employees (LastName, FirstName, Title, HireDate, ReportsTo, Photo) " +
"Values(@LastName, @FirstName, @Title, @HireDate, @ReportsTo, @Photo)", nwindConn); addEmp.Parameters.Add("@LastName", SqlDbType.NVarChar, 20).Value = lastName;
addEmp.Parameters.Add("@FirstName", SqlDbType.NVarChar, 10).Value = firstName;
addEmp.Parameters.Add("@Title", SqlDbType.NVarChar, 30).Value = title;
addEmp.Parameters.Add("@HireDate", SqlDbType.DateTime).Value = hireDate;
addEmp.Parameters.Add("@ReportsTo", SqlDbType.Int).Value = reportsTo; addEmp.Parameters.Add("@Photo", SqlDbType.Image, photo.Length).Value = photo; nwindConn.Open(); addEmp.ExecuteNonQuery(); nwindConn.Close();
} public static byte[] GetPhoto(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs); byte[] photo = br.ReadBytes((int)fs.Length); br.Close();
fs.Close(); return photo;
}
}