C#保存图片!2002

C#保存图片!2002 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: C# code namespace add.compents { using System; using System.Data; using System.Drawing; using System.Drawing.Drawing2D; using System.Drawing.Imaging; using System.IO; using System.Net; using System.Web; using System.Text.RegularExpressions; public class UploadHelper { private UploadHelper() { } ///

/// 判断文件扩展名是否为允许的 ///

/// /// //public static bool IsAllowedFileExtension(string fileName) { // string extsAllowed = Config.AllowedFileExtenstions; // return Regex.IsMatch(fileName, // @"^.*[" + extsAllowed + "]$", // RegexOptions.Compiled | // RegexOptions.Singleline | // RegexOptions.IgnoreCase); //} ///

/// 验证文件名中是否包含不合法字符 ///

/// //public static bool IsLegalFileName(string fileName) { // return Regex.IsMatch(fileName, @"^[a-z|A-Z|0-9|_|\-|\.]*$", // RegexOptions.Compiled); //} ///

/// 创建一个随机的文件名 ///

/// /// public static string CreateRandomFileName(string exfilename,string extension) { Random rnd = new Random((int)DateTime.Now.Ticks); //Random rnd = new Random(); string rndFileName = rnd.Next(1,100).ToString(); //rndFileName = rndFileName.Substring(0, 6); //return exfilename + DateTime.Now.ToString("yyyyMMddhhmmss") + rndFileName + extension; return exfilename + DateTime.Now.ToString("yyyyMMddhhmmss") + rndFileName; } ///

/// Upload a file. ///

/// /// The fileName generated in the server. /// true/false /// created by Neil, 2006-1-14 public static bool UploadFile(HttpPostedFile file, string uploadpath,string exfilename,out string saveAsFileName, out string errorMessage) { string fname = Path.GetFileName(file.FileName); saveAsFileName = ""; errorMessage = ""; if (fname.Length > 0) { //bool allowed = IsAllowedFileExtension(fname); //if (!allowed) { // errorMessage = "文件的扩展名不符合要求:" + fname; // return false; //} //if (!CheckSize(file,Config.fileSize)) { // errorMessage = "文件超出规定大小，不能超过 "+Config.fileSize+"K"; // return false; //} string extension = fname.Substring(fname.LastIndexOf(".")); saveAsFileName = CreateRandomFileName(exfilename, extension) + fname; try { string path = uploadpath + "\\" + saveAsFileName; file.SaveAs(path); } catch (Exception ex) { errorMessage = "上传文件失败:" + fname; throw ex; } return true; } else { errorMessage = "您选择的上传文件不包含有效的文件名。"; return false; } } //public static bool UploadFile1(HttpPostedFile file, out string saveAsFileName, out string errorMessage) //{ // string fname = Path.GetFileName(file.FileName); // saveAsFileName = ""; // errorMessage = ""; // if (fname.Length > 0) // { // bool allowed = IsAllowedFileExtension(fname); // if (!allowed) // { // errorMessage = "文件的扩展名不符合要求:" + fname; // return false; // } // if (!CheckSize(file, Config.fileSize)) // { // errorMessage = "文件超出规定大小，不能超过" + Config.fileSize + "K"; // return false; // } // string extension = fname.Substring(fname.LastIndexOf(".")); // saveAsFileName = CreateRandomFileName(extension); // try // { // string path = Config.photoUploadPath + "/" + saveAsFileName; // file.SaveAs(HttpContext.Current.Server.MapPath(path)); // } // catch (Exception ex) // { // errorMessage = "上传文件失败:" + fname; // throw ex; // } // return true; // } // else // { // errorMessage = "您选择的上传文件不包含有效的文件名。"; // return false; // } //} private static bool CheckSize(HttpPostedFile file,string filesize) { return (file.ContentLength <= Convert.ToInt32(filesize)*1024); /*string fnlower = file.FileName.ToLower(); // 图片小于 200k if (fnlower.EndsWith(".jpg") || fnlower.EndsWith(".jpeg")) { } else if (fnlower.EndsWith(".mpg") || fnlower.EndsWith(".mpeg")) { // 视频小于 2M return (file.ContentLength <= 2097152); } else { return false; }*/ } //public static string MakeAvailableFileName(string fileName) { // string filenamelower = fileName.ToLower(); // string extension = filenamelower.Substring(filenamelower.LastIndexOf(".")); // string fn = Path.GetFileNameWithoutExtension(fileName); // string newFileName = fileName; // int suffix = 1; // while (File.Exists(Path.Combine(HttpContext.Current.Server.MapPath(Config.UploadPath), newFileName))) { // newFileName = fn + "_" + suffix.ToString() + extension; // suffix++; // } // return newFileName; //} //public static void DeleteFile(string fileName) //{ // string uploadPath = Config.UploadPath; // string deleteFileName = Path.Combine(uploadPath, fileName); // try // { // if (File.Exists(deleteFileName)) File.Delete(deleteFileName); // } // catch // { // // silently swallow the exception // } //} } } using System; using System.Collections.Generic; using System.ComponentModel; 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; cmd.CommandText = "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，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) { } } } }