关于.net(C#)中的跨进程访问的问题
发布时间:2020-12-15 05:51:09 所属栏目:百科 来源:网络整理
导读:namespace process_image { public partial class jszg_upload : Form { static bool stop_flag = false; public jszg_upload() { InitializeComponent(); } private void upload_button1_Click(object sender,EventArgs e) { stop_flag = false; if (this.ch
namespace process_image { public partial class jszg_upload : Form { static bool stop_flag = false; public jszg_upload() { InitializeComponent(); } private void upload_button1_Click(object sender,EventArgs e) { stop_flag = false; if (this.checkBox1.Checked) { String connectionString = "连接串"; using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); SqlCommand cmd = new SqlCommand(" update my_jszg set filemime=null,filebody = null",conn); cmd.ExecuteNonQuery(); conn.Close(); } } new Thread(uploadImageToDB).Start(); }//end upload_button1_Click void uploadImageToDB() { //第一步:发现文件夹下面的文件及数量 DirectoryInfo myFolder = new DirectoryInfo("bcd"); FileInfo[] myFiles = myFolder.GetFiles(); this.richTextBox1.Text = "从文件夹中发现了:" + myFiles.Length.ToString() + " 个文件!" + "n"; this.jindutiao_progressBar1.Maximum = myFiles.Length; //第二步:开始上传文件 String connectionString = "连接串"; using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); for (int i = 0; i < myFiles.Length; i++) { if(stop_flag) break; //进度条 this.jindutiao_progressBar1.Value = i + 1; this.pictureBox1.ImageLocation = myFiles[i].FullName; this.richTextBox1.Text = myFiles[i].Name + "n" + this.richTextBox1.Text; this.baifenbi_label1.Text = ((((i + 1) * 1.0) /myFiles.Length) * 100) + "%"; //上传实际的数据image/jpeg SqlCommand cmd = new SqlCommand(" update my_jszg set filemime='image/jpeg',filebody = @myfilebody from my_jszg where 证件号码=@myzjhm",conn); byte[] fb = new byte[myFiles[i].Length]; BinaryReader br = new BinaryReader(myFiles[i].OpenRead()); br.Read(fb,(int)myFiles[i].Length); cmd.Parameters.AddWithValue("@myfilebody",fb); cmd.Parameters.AddWithValue("@myzjhm",myFiles[i].Name.Substring(0,myFiles[i].Name.LastIndexOf('.'))); cmd.ExecuteNonQuery(); br.Close(); }//end for conn.Close(); } MessageBox.Show("所有的文件上传完毕!"); } //停止上传 private void stop_button_Click(object sender,EventArgs e) { stop_flag=true; } } } 在此代码中,对一个控件的访问如: this.richTextBox1.Text = myFiles[i].Name + "n" + this.richTextBox1.Text; 仅限在一个线程中,如果在两个进程中对控件访问将会出错!如不能在程序自己的线程 和 uploadImageToDB 线程中访问。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |