VSTO學習筆記（四）從SharePoint 2010中下載文件

上一次我們開發了一個簡單的64位COM加載項，雖然功能很簡單，但是包括了開發一個64位COM加載項的大部分過程。本次我們來給COM加載項添加一些功能：從SharePoint 2010的文檔庫中下載一個Excel文檔到本地。

示例代碼下載

本系列所有示例代碼均在 Visual Studio 2010 Ultimate RC + Office 2010 Professional Plus Beta x64 上測試通過。

1、首先創建一個Shared AddIn項目（具體細節請參閱上一篇文章）：

2、添加引用：

Microsoft.SharePoint

System.Windows.Forms

System.Drawing

System.DirectoryServices

3、在Connect類中創建Application和COMAddIn的實例：

代碼

    /// <summary>
    ///   The object for implementing an Add-in.
    /// </summary>
    /// <seealso class='IDTExtensibility2' />
    [GuidAttribute("6D3788F4-9529-429E-BA5D-09695F85687A"), ProgId("SimpleExcelServicesDemo.Connect")]
    public class Connect : Object, Extensibility.IDTExtensibility2
    {
        private Microsoft.Office.Interop.Excel.Application app;
        private Microsoft.Office.Core.COMAddIn addIn;

3、在OnConnection事件里初始化：

代碼

        public void OnConnection(object application, Extensibility.ext_ConnectMode connectMode, object addInInst, ref System.Array custom)
        {
            this.app = application as Microsoft.Office.Interop.Excel.Application;
            this.addIn = addInInst as Microsoft.Office.Core.COMAddIn;
        }

4、在OnStartupComplete事件中設置一個按鈕，關聯事件處理邏輯：

代碼

        public void OnStartupComplete(ref System.Array custom)
        {
            CommandBars commandBars;
            CommandBar standardBar下載數據;
            CommandBarButton simpleButton下載數據;
            commandBars = this.app.CommandBars;

            // Get the standard CommandBar from Word
            standardBar下載數據 = commandBars["Standard"];

            try
            {
                // try to reuse the button is hasn't already been deleted
                simpleButton下載數據 = (CommandBarButton)standardBar下載數據.Controls["下載數據"];
            }
            catch (System.Exception)
            {
                // If it's not there add a new button
                simpleButton下載數據 = (CommandBarButton)standardBar下載數據.Controls.Add(1);
                simpleButton下載數據.Caption = "下載數據";
                simpleButton下載數據.Style = MsoButtonStyle.msoButtonCaption;
            }

            // Make sure the button is visible
            simpleButton下載數據.Visible = true;
            simpleButton下載數據.Click += new _CommandBarButtonEvents_ClickEventHandler(btnDownload_Click);

            standardBar下載數據 = null;
            commandBars = null;
        }

5、做一個域用戶驗證，當用戶輸入了合法的與用戶名和密碼后，才允許下載。這里添加了一個WindowsForm到項目中:

6、域用戶驗證邏輯，我本機是一臺域控制器BROOKS.COM，使用的靜態IP: 192.168.1.100，【LDAP://192.168.1.100/DC=BROOKS,DC=com】是LDAP的路徑語法：

代碼

        private bool fn數據驗證()
        {
            if (this.txt用戶名.Text.Trim() == string.Empty)
            {
                MessageBox.Show("用戶名不能為空！");
                this.txt用戶名.Focus();
                return true;
            }

            if (this.txt密碼.Text.Trim() == string.Empty)
            {
                MessageBox.Show("密碼不能為空！");
                this.txt密碼.Focus();
                return true;
            }

            if (this.fn域用戶驗證(@"LDAP://192.168.1.100/DC=BROOKS,DC=com", this.txt用戶名.Text.Trim(), this.txt密碼.Text.Trim()))
            {
                MessageBox.Show("您輸入的用戶名或密碼錯誤，請重新輸入！");
                this.txt密碼.Clear();
                this.txt密碼.Focus();
                return true;
            }
            return false;
        }

        private bool fn域用戶驗證(string path, string username, string pwd)
        {
            try
            {
                DirectoryEntry entry = new DirectoryEntry(path, username, pwd);
                DirectorySearcher search = new DirectorySearcher(entry);
                search.Filter = "(SAMAccountName=" + username + ")";
                SearchResult result = search.FindOne();

                if (null == result)
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            catch
            {
                return true;
            }
        }

7、使用Windows Server 2008 R2的AD管理器創建一個域用戶：test

8、在Connect中編寫下載文件邏輯：

SharePoint 2010 網站是：http://brookspc/sites/doc，我們要下載的就是其Document庫中的Excel Services Test.xlsx。

代碼

        private void fn下載文件()
        {
            //保存文件
            using (SPSite site = new SPSite("http://brookspc/sites/doc"))
            {
                SPWeb web = site.OpenWeb();
                string __fileName = "http://brookspc/sites/doc/Documents/Excel Services Test.xlsx";
                SPFile file = web.GetFile(__fileName);
                string __localFilePath = @"C:\ExcelServices.xlsx";
                //將文件下載到本地
                byte[] content = file.OpenBinary();
                if (File.Exists(__localFilePath))
                {
                    File.Delete(__localFilePath);
                }
                FileStream fs = new FileStream(__localFilePath, FileMode.Create);
                fs.Write(content, 0, content.Length);
                fs.Flush();
                fs.Close();
            }
        }

9、按鈕事件處理邏輯：

代碼

        public void btnDownload_Click(CommandBarButton sender, ref bool cancelDefault)
        {
            FrmLogin login = new FrmLogin();
            if (login.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                this.fn下載文件();
            }
        }

10、編譯一下，安裝生成的setup.exe：