动态进行多个搜索同步怎么操作？

Question

BackgroundWorker

Answer 1

http://www.cnblogs.com/caicaihui/archive/2013/03/17/2964422.html这个例子没有看懂

Answer 2

最简单的，在循环中加一个
Application.DoEvents();
就可以防止界面失去响应啦。

Answer 3

救命啊，不知道为什么会出现崩溃，搜索结果少的情况不会，搜索结束一遍再按搜索，反复进行发现抛进结果竟然会出现搜索结果数量不一致的情况，再多几遍搜索竟然出现崩溃退出。
如果一次搜索结果太多也会出现崩溃退出，不知道是哪里出现了问题。        private List<BackgroundWorker> bws = new List<BackgroundWorker>();
        private ArrayList listReasult = new ArrayList();
        private StringBuilder SearchType = null;
        private string searchKey = string.Empty;        private void toolStripButton1_Click(object sender, EventArgs e)
        {
            if (this.sText.Text.Trim() != "输入多个关键字间用%分开" && this.sText.Text.Trim() != "")
            {
                this.sText.Text = this.sText.Text.ToUpper().Trim();
                this.sText.SelectionStart = this.sText.Text.Length;
                this.searchKey = this.sText.Text;
                this.SearchType = new StringBuilder();
                foreach (ToolStripMenuItem tsm in this.toolStripDropDownButton2.DropDownItems)
                {
                    if (tsm.Checked == true)
                    {
                        if (SearchType.Length == 0)
                        {
                            SearchType.Append("FileType='" + tsm.Text + "'");
                        }
                        else
                        {
                            SearchType.Append(" or FileType='" + tsm.Text + "'");
                        }
                    }
                }
                if (SearchType.Length == 0)
                {
                    MessageBox.Show("查询的搜索类型不能为空", "图纸查询", MessageBoxButtons.OK, MessageBoxIcon.Hand);
                    return;
                }
                this.toolStripLabel2.Visible = true;
                this.toolStripLabel2.Text = "Searching...";
                this.toolStripButton1.Visible = false;
                this.toolStripButton2.Visible = true;
                this.listView.Items.Clear();
                this.listView.BeginUpdate();
                foreach (ToolStripMenuItem tsm in this.toolStripDropDownButton1.DropDownItems)
                {
                    if (tsm.Checked == true)
                    {
                        BackgroundWorker search = new BackgroundWorker();
                        search.WorkerSupportsCancellation = true;
                        search.DoWork += new DoWorkEventHandler(search_DoWork);
                        search.RunWorkerCompleted += new RunWorkerCompletedEventHandler(search_RunWorkerCompleted);
                        bws.Add(search);
                        search.RunWorkerAsync(tsm.Text);
                    }
                }
                if (this.bws.Count == 0)
                {
                    MessageBox.Show("请选择图纸的搜索范围", "图纸查询", MessageBoxButtons.OK, MessageBoxIcon.Hand);
                }
            }
            else
            {
                MessageBox.Show("查询的关键字不能为空", "图纸查询", MessageBoxButtons.OK, MessageBoxIcon.Hand);
            }  
        }        private void toolStripButton2_Click(object sender, EventArgs e)
        {
            if (this .bws .Count !=0)
            {
                this.toolStripLabel2.Text = "SearchCanceling...";
                for (int i = 0; i < bws.Count; i++)
                {
                    this.bws[i].CancelAsync();
                }
            }
        }        private void search_DoWork(object sender, DoWorkEventArgs e)
        {
            string con = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + this.Tag + @"\" + e.Argument + ".mdb;Jet OLEDB:Database Password=Pleasecall110";
            string sql = @"select FileDate,FileName,FileType,ViewPath,NetPath from [" + e.Argument + "] where (FileName like '%" + searchKey + "%') and (" + SearchType.ToString() + ")";
                OleDbConnection dataCon = new OleDbConnection(con);
                OleDbCommand dataCmd = null;
                OleDbDataReader dataRead = null;
                try
                {
                    if (dataCon.State == ConnectionState.Closed) { dataCon.Open(); }
                    dataCmd = new OleDbCommand(sql, dataCon);
                    dataRead = dataCmd.ExecuteReader();
                    while (dataRead.Read())
                    {
                        if (((BackgroundWorker)sender).CancellationPending)
                        {
                            e.Cancel = true;
                            break;
                        }
                        string[] list = new string[5];
                        list[0] = (string)dataRead["FileName"].ToString();
                        list[1] = (string)dataRead["FileDate"].ToString();
                        list[2] = (string)dataRead["ViewPath"].ToString();
                        list[3] = (string)dataRead["FileType"].ToString();
                        list[4] = (string)dataRead["NetPath"].ToString();
                        this.listReasult.Add(list);
                    }
                }
                catch { }
                finally
                {
                    if (dataRead != null) { dataRead.Close(); }
                    if (dataCmd != null) { dataCmd.Dispose(); }
                    if (dataCon.State == ConnectionState.Open) { dataCon.Close(); }
                }            
        }        private void search_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            bws.Remove(sender as BackgroundWorker);
            if (bws.Count == 0)
            {
                foreach (string[] list in this.listReasult)
                {
                    ListViewItem lv = new ListViewItem(new string[] { list[0], DateTime.Parse(list[1]).ToString("yyyy-MM-dd HH:mm"), list[2] });
                    lv.ImageKey = list[3];
                    lv.Tag = list[4];
                    this.listView.Items.Add(lv);
                }
                this.toolStripButton1.Visible = true;
                this.toolStripButton2.Visible = false;
                this.toolStripLabel2.Text = "共搜索到 " + this.listReasult.Count + " 个结果";
                this.listReasult.Clear();
                this.listView.EndUpdate();
                if (this.listView.Items.Count != 0)
                {
                    string xx = string.Empty;
                    foreach (object key in this.sText.Items)
                    {
                        if (this.sText.Text == key.ToString())
                        {
                            xx = key.ToString();
                            break;
                        }
                    }
                    if (xx == string.Empty)
                        this.sText.Items.Add(this.sText.Text);
                }
                else
                {
                    MessageBox.Show("没有查询到结果，请更改查询条件再试！", "图纸查询", MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
            }
        }