C#保存图片

保存图片两种办法，一种字节流存，一种存路径。

大多数人的做法是保存路径，这也是最好的方法。

用字节流操作很繁琐，而且效率不高。。。

两种方法的优势很明显，如果学习，两个都可以看看，如果是项目中肯定选择后者。给你一个帮助类吧...无论是图黑市文件都可以用：

using System;

using System.Collections.Generic; using ponentModel; using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms; using System.Data.SqlClient;

using System.IO;

namespace WindowsFormsApplication1

{

public partial class Form1 : Form

{

string inputFile = string.Empty;

static SqlConnection conn = new SqlConnection("Data Source=.;Initial Catalog=Northwind;User ID=sa;Password=sa"); public Form1()

{

InitializeComponent();

}

private void richTextBox1_TextChanged(object sender, EventArgs e)

{

richTextBox1.AppendText("");

}

private void button1_Click(object sender, EventArgs e)

{

openFileDialog1.Filter = "图像文件(*.jpg)|*.jpg|gif文件(*.gif)|*.*|所有文件(*.*)|*.*";

openFileDialog1.Title = "Select a JPG File";

openFileDialog1.FileName = "";

if (openFileDialog1.ShowDialog() == DialogResult.OK)------------------------------------选择本地文件

{

richTextBox1.Text = openFileDialog1.FileName;

inputFile = openFileDialog1.FileName;

InsertDB(inputFile);

}

}

private static void InsertDB(string file)

{

FileInfo finfo = new FileInfo(file); //绝对路径

if (finfo.Exists)

{

SqlCommand cmd = new SqlCommand();

cmd.Connection = conn;

mandText = "Insert into Categories(CategoryName,Picture) values('test',@Content)";

cmd.Parameters.Add("@Content", SqlDbType.Image, (int)finfo.Length, "Image字段名"); //注意，此处参数Size为写

入的字节数

//读取文件内容，写入byte数组---------------------------------------------------将文件存入数据库图片字段

byte[] content = new byte[finfo.Length];

FileStream stream = finfo.OpenRead();

stream.Read(content, 0, content.Length);

stream.Close();

cmd.Parameters["@Content"].Value = content; //为参数赋值

try

{

conn.Open();

cmd.ExecuteNonQuery();

}

finally

{ conn.Close();}

}

}

private void button2_Click(object sender, EventArgs e)

{

SqlCommand myCommand = new SqlCommand("Select top 1 Picture from Categories order by CategoryID desc", conn);

--------------------------------------------------------------------------------从数据库中找到图片字段

try

{

conn.Open();

SqlDataReader myDataReader;

myDataReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection);

if (myDataReader.Read())

{

byte[] bin = (byte[])myDataReader["Picture"];

MemoryStream stream = new MemoryStream(bin, true);

stream.Write(bin, 0, bin.Length);

pictureBox1.BackgroundImageLayout = ImageLayout.Center;

pictureBox1.Image = Bitmap.FromStream(stream); ---------------------------------------------------将图片显示在pictureBox

stream.Close();

}

conn.Close(); }

catch (SqlException SQLexc)

{ } } }

}