ASP.Net Tips n Tricks

1) Get the full file path (with name) in ASP.Net's FileUpload control.

FileUpload1.PostedFile.FileName returns full file path (including file name),
FileUpload1.FileName returns only file name.

2) Password Validation

Following code snippet display password validation at Client side (JavaScript).
Here password must contains Non-AlphaNumeric character(s) and length should be greater than 6.

<asp:TextBox ID="txtPassword" runat="server" Width="270px" 
Enabled="true"></asp:TextBox>
<asp:CustomValidator ID="valPasswd" runat="server" 
ControlToValidate="txtPassword" ClientValidationFunction="validatePassword" 
Display="Dynamic" 
ErrorMessage="* Inadequate password strength."></asp:CustomValidator>

<script type="text/javascript">

        function validatePassword(oSrc,args)
        {
            var isValid = false;
            
            var regExp =  /\W/;   //  /[^a-zA-Z0-9]/;
            if( (regExp.test(args.Value)) && (args.Value.length > 6) )
                isValid = true;
           
            args.IsValid = isValid;
        }

</script>

3) How to get GridView's RowIndex (current row index) in GridView's RowCommand event:

There are two ways to find rowindex, as per me second is comparatively good one
because we need not to do control.Parent.Parent

int rowIndex 
    = ((GridViewRow)((Control)e.CommandSource).Parent.Parent).RowIndex; 
 
int rowIndex 
    = ((GridViewRow)((Control)e.CommandSource).NamingContainer).RowIndex;

4) How to search a particular object in a Generic List:

Consider we have a generic list that holds an organization's employees objects,
and we find to a particular employee object based on some input like employee ID.
Here is the code:

List employees = ""; //Logic to fill employees list.
//Search a particular employee based on employee code 
//[Here EmployeeCode is one of the variable or properties in Employee class]
Employee employee = employees.Find(delegate(Employee emp) 
                      { return emp.EmployeeCode == inputValue; });

5) How to find control(s) in ASP.Net GridView's EmptyDataTemplate?

If we are using ASP.Net GridView for displaying records, then to display GridView with no record we have to use EmptyDataTemplate. Inside that we will write all our required controls.

Consider a case... in which EmptyDataTemplate contains a textbox and a button.
If we click button, then GridView's OnRowCommand event will fire.

In GridView_OnRowCommand method to get textbox control we can follow one of the following approaches:

//Approach 1
TextBox txt 
      = (TextBox)gridviewSP.Controls[0].Controls[0].Controls[0].Controls[1];

//Approach 2
GridViewRow row 
      = (GridViewRow)((ImageButton)e.CommandSource).NamingContainer;
TextBox txt = row.FindControl("txtName");

As per me second approach is good one, because we need to do blind control search.

In second approach first we are getting GridViewRow, that contains textbox and button. Then in that GridViewRow, with FindControl function find our required textbox.


6) ASP.Net's GridView sorting logic

//C# code

//Call to get GridView's SortOrder and SortExpression...
string sortExpression = e.SortExpression;
bool sorting = GetSortDirection(sortExpression) == "ASC" ? true : false;
.
.


.
.
/// <summary>
/// Gets sort direction for gridview sorting
/// </summary>
/// <param name="column"></param>
/// <returns></returns>
string GetSortDirection(string column)
{
    // By default, set the sort direction to ascending.
    string sortDirection = "ASC";
 
    // Retrieve the last column that was sorted.
    string sortExpression = ViewState["SortExpression"] as string;
 
    if (sortExpression != null)
    {
        // Check if the same column is being sorted.
        // Otherwise, the default value can be returned.
        if (sortExpression == column)
        {
            string lastDirection = ViewState["SortDirection"] as string;
            if ((lastDirection != null) && (lastDirection == "ASC"))
            {
                sortDirection = "DESC";
            }
        }
    }
 
    // Save new values in ViewState.
    ViewState["SortDirection"] = sortDirection;
    ViewState["SortExpression"] = column;
 
    return sortDirection;
}

7) Operation related to ASP.Net's TextBox with TextMode set to Password :
If we set the TextMode property of ASP:TextBox to Password, then we can't directly access the Text property of TextBox after page postback. Its a known issue and one of the solution is to use Attributes of textbox. We can set the TextBox's Attributes in TextBox_PreRender event and consume its value anywhere we want by using the stored value in Attributes.

<!-- HTML code -->
<asp:TextBox ID="TextBoxPassword" OnPreRender="TextBoxPassword_PreRender" 
              TextMode="Password" runat="server" Width="150px"></asp:TextBox>


//C# code

protected void TextBoxPassword_PreRender(object sender, EventArgs e)
{
    TextBoxPassword.Attributes.Add("value", TextBoxPassword.Text);
}

protected void ButtonAddUser_Click(object sender, EventArgs e)
{ 
    String password = TextBoxPassword.Attributes["value"];
}

8) Operation related to ASP.Net's GridView and DataTable :
This section covers DataTable and its usage in ASP:GridView, especially the Primary Key column and Find functionality of DataTable. [Code are self-explainatory with comments]

//C# code

protected void Page_Load(object sender, EventArgs e)
{
    if (!Page.IsPostBack)
    {
        //Get the DataTable instance and store it
        //in ViewState to be used later on.
        if (ViewState["EmpDataTable"] == null)
        {
            ViewState["EmpDataTable"] = CreateDataTable();
        }

        dataTableEmps = (DataTable)ViewState["EmpDataTable"];

        //Set the DataSource and Bind the Grid
        GridViewEmps.DataSource = dataTableEmps;
        GridViewEmps.DataBind();
     }
}


//Create and return a DataTable and its schema.
DataTable CreateDataTable()
{
   //Create a DataTable, then add two Columns in it.
   DataTable dataTable = new DataTable("Employeess");

   dataTable.Columns.Add("EmployeeName", Type.GetType("System.String"));
   
   DataColumn primaryColumn 
          = new DataColumn("EmployeeID", Type.GetType("System.String"));
   dataTable.Columns.Add(primaryColumn);

   //Set the PrimaryKey in DataTable 
   //(to be used in Find functionality of DataTable)
   primaryColumn.Unique = true;
   dataTable.PrimaryKey = new DataColumn[] { primaryColumn };

   return dataTable;
}

//GridView's OnRowDeleting event
protected void GridViewEmps_RowDeleting(object sender
   , GridViewDeleteEventArgs e)
{
   //Get the control value
   string empID 
   = ((Label)GridViewEmps.Rows[e.RowIndex]
      .FindControl("LabelGridViewEmpID")).Text;

   //Get the DataTable instance
   if (ViewState["EmpDataTable "] == null)
       ViewState["EmpDataTable "] = CreateDataTable();
   else
       dataTableEmps = (DataTable)ViewState["EmpDataTable "];

   //Find the row, which we want to delete. 
   //Only pass the value of Primary key column.
   DataRow row = dataTableEmps.Rows.Find(empID);

   dataTableEmps.Rows.Remove(row);
   GridViewEmps.DataSource = dataTableEmps;
   GridViewEmps.DataBind();
}


<!-- HTML code -->
<asp:GridView ID="GridViewEmps" runat="server" 
          AutoGenerateColumns="false" 
          OnRowDeleting="GridViewEmps_RowDeleting">
   <Columns>
      <asp:TemplateField HeaderText="Name">
         <ItemTemplate>
            <asp:Label ID="LabelGridViewEmpName" runat="server" 
                      Text='<%# Bind("EmployeeName") %>'></asp:Label>
         </ItemTemplate>
      </asp:TemplateField>
      <asp:TemplateField HeaderText="LoginName" Visible="false">
         <ItemTemplate>
            <asp:Label ID="LabelGridViewEmpID" runat="server" 
                      Text='<%# Bind("EmployeeID") %>'></asp:Label>
         </ItemTemplate>
      </asp:TemplateField>
   </Columns>
</asp:GridView>

9) Function to convert a image/text file into byte array

private byte [] StreamFile(string filename)
{
   FileStream fs = new FileStream(filename, FileMode.Open,FileAccess.Read);

   // Create a byte array of file stream length
   byte[] dataArray = new byte[fs.Length];

   //Read block of bytes from stream into the byte array
   fs.Read(dataArray,0,System.Convert.ToInt32(fs.Length));

   //Close the File Stream
   fs.Close();
   return dataArray; //return the byte data
}

10) Code to add a new XmlNode / XmlElement in XmlDocument:

string strFilename = "Employees.xml";
XmlDocument xmlDoc = new XmlDocument();

if (File.Exists(strFilename))
{
    xmlDoc.Load(strFilename);

    XmlElement xElement = xmlDoc.CreateElement("Employee");
    string strNewEmployee = "<ID>9</ID>" +
                            "<Name>Avi</Name>" +
                            "<Age>25</Age>";

    xElement.InnerXml = strNewEmployee;
    xmlDoc.DocumentElement.AppendChild(xElement);

    xmlDoc.Save("Employees.xml");
}

Operations related to SharePoint's Column type Person or Group

In this post I discussed how we can fetch records from SPListItem's column type Person or Group and stored information back into that column.

Here in following method first I am creating the SPUser by using EnsureUser method of SPSite and then adding that SPUser in SPListItem of SPList. Then I am fetching that SPUser from the SPListItem.

(In Folloing method codes with comments are self-explainatory)

    /// <summary>
    /// Working with with column of type [Person OR Group]
    /// </summary>
    void user()
    {
        //SPListItem spListItem;

        string loginName = "DOMAIN\\USERNAME";
        //Assign SPUser in your custom column and 
        //also its Login name (string) in seperate column 
        //(for ease in development operation)
        spListItem["User"] = oWebsite.EnsureUser(loginName);
        spListItem["UserLoginName"] = loginName;


        //Fetch SPUser values from SPColumn
        SPFieldUserValueCollection values 
              = (SPFieldUserValueCollection)spListItem["User"];
        loginName = values[0].User.LoginName;
    }

Note : From UI control point of view, we can use SharePoint's PeoplePicker control to enter and validate SPUser.

SharePoint's ListViewWebPart --- Part 2

In continuation with previous post SharePoint's ListViewWebPart.

In this post I discussed how we can apply complex filter in SharePoint's ListView WebPart.

In one of appliation I was using SharePoint's ListView webpart in an aspx page to display the records from SPList. In that page I am also providing a search funtionality. Based on the applied search I am changing the records displayed in ListView webpart.

So the challenge was to apply the complex search filter on ListView webpart programmatically and dynamically. ListView webpart exposes FilterString property but in that we can apply simple filter and that only to one column (as per my knowledge).

So to apply complex filter, first we have to get the SPView from which we are populating data in ListViewWebPart. Then change the Query property of SPView as per our requirement.

In following method I implemented the above mentioned logic (codes with comments are self-explainatory).

    /// <summary>
    /// Search functionality OR Apply complex filter in SharePoint's ListView WebPart
    /// </summary>
    /// <param name="eventArgument"></param>
    void searchRecord(string flag)
    {
        try
        {
            SPSite oWebsite = SPContext.Current.Web;
            SPList oList = oWebsite.Lists["LISTNAME"];
            //oListViewWP  is ListView Webpart's ID

            oWebsite.AllowUnsafeUpdates = true;

            //Clear Search filter OR revert back SPView modification.
            if (flag == "false")
            {
                //Listview webpart related settings
                oListViewWP.ListName = oList.ID.ToString("B").ToUpper();
                
                //Set SPView for Listview WP
                SPView view = oList.Views["SPView_NAME"];
                view.Query = string.Empty;
                view.Update();

                oListViewWP.ViewGuid = view.ID.ToString("B").ToUpper();
                oListViewWP.GetDesignTimeHtml();
            }
            else
            {
                //Build the SPQuery
                StringBuilder strbPreQuery 
                = new StringBuilder("<Where><Contains>");
               
                StringBuilder strbPostQuery 
                = new StringBuilder("</Value></Contains></Where>");

                string strQueryKeyword = string.Empty;

                switch (drpSearchKeywordType.SelectedValue)
                {
                    case "Contact Number":
                        strQueryKeyword 
                          = "<FieldRef Name='Contact_x0020_Number'/>
                            <Value Type='Text'>";
                        break;

                    case "Email ID":
                        strQueryKeyword 
                          = "<FieldRef Name='Email_x0020_ID'/>
                            <Value Type='Text'>";
                        break;
                }

                //Build SPQuery
                SPQuery oQuery = new SPQuery();
                oQuery.Query 
                  = strbPreQuery.ToString() + strQueryKeyword +
                    txtSearchKeyword.Text + strbPostQuery.ToString();
                SPListItemCollection itemCol = oWebsite.Lists[spListName].GetItems(oQuery);

                if (itemCol.Count > 0)
                {
                    //Listview webpart related settings
                    oListViewWP.ListName = oList.ID.ToString("B").ToUpper();
                    
                    //Modifying SPView as per required SPQuery.
                    SPView view = oList.Views["SPView_NAME"];
                    view.Query = oQuery.Query;
                    view.Update();

                    //Modifying ListView WebPart as changed SPView
                    oListViewWP.ViewGuid = view.ID.ToString("B").ToUpper();
                    oListViewWP.GetDesignTimeHtml();
                }
            }

            oWebsite.AllowUnsafeUpdates = false;
        }
        catch (Exception ex)
        {
        }
    }

How to programmatically attach a document or file in a SPListItem

How to programmatically attach a document or file in a SPListItem

In this post I discussed, how we can programmatically attach a document or file in a SPListItem of SPList (SharePoint's List).

Following method contains the logic to attach the document / file (codes with comments are self-explainatory).

    /// <summary>
    /// Programmatically Attach document in SPDocument Library 
    /// </summary>
    void documentAttachmentInSPList()
    {
        //SPListItem spListItem = null; //write code to get the SPListItem.
        //fileUpload is control ID of ASP.Net FileUpload control        
        if (!string.IsNullOrEmpty(fileUpload.FileName))
        {
            //Get file extension ( *.doc OR *.docx )
            string fileExtension 
             = fileUpload.FileName.Substring(fileUpload.FileName.IndexOf("."));

            //FILENAME is file name visible in SPListItem
            //Check file is already added or not. If added then delete it.
            for (int i = 0; i < spListItem.Attachments.Count; i++)
            {
                if ((spListItem.Attachments[i] != null) 
                    && (spListItem.Attachments[i].Equals("FILENAME" + fileExtension)))
                {
                    spListItem.Attachments.Delete("FILENAME" + fileExtension);
                    break;
                }
            }

            //Attach the file.
            spListItem.Attachments.Add("FILENAME" + fileExtension, fileUpload.FileBytes);
            
            //LISTNAME is SPList's name
            //See the attached file as link in user-created custom column.
            string attachmentURL = Request.Url.Scheme + "://" + Request.Url.Authority
                   + "/Lists/" + "LISTNAME" + "/Attachments/" + spListItem.ID + "/";

            spListItem["Attached File"] 
              = attachmentURL + "FILENAME" + fileExtension + ", View FILE";
        }
    }

How to programmatically upload a document in a SPDocumentLibrary

In this post I discussed, how we can programmatically upload a document in a SPDocumentLibrary (SharePoint's document library).

Following method contains the logic to upload the document (codes with comments are self-explainatory).

    /// <summary>
    /// Programmatically UPLoad document in SPDocument Library 
    /// </summary>
    void documentUploadInSPDocumentLibrary()
    {        
        //fileUpload is ASP.Net FileUpload control.
        if (!string.IsNullOrEmpty(fileUpload.FileName))
        {
            SPSite oWebsite = SPContext.Current.Web;
            oWebsite.AllowUnsafeUpdates = true;
            SPDocumentLibrary docLib 
                = oWebsite.Lists["DOCLIB_NAME"] as SPDocumentLibrary;

            //Get file extension ( *.doc OR *.docx )
            string fileExtension 
                = fileUpload.FileName.Substring(fileUpload.FileName.IndexOf("."));
            byte[] fileBytes = fileUpload.FileBytes;
            string destUrl 
                = docLib.RootFolder.Url + "/" + "MyFileName" + fileExtension;
            SPFile destFile = docLib.RootFolder.Files.Add(destUrl, fileBytes, true);
            destFile.Update();

            oWebsite.AllowUnsafeUpdates = true;
        }
    }

Check Record or FileName in a SPDocument Library

In this post I discussed how we can check whether a particular record / filename exist in a SPDocumentLibrary (SharePoint's document library) or not.

In the following method, first I discussed the 4 approaches suggested in following blog/forum, then the 5th apporach (in which I used SPQuery).

According to me the 5th and last approach is good-one because it would't raise an Exception.

    /// <summary>
    /// Check FileName/Records in SPDocumentLibrary
    /// </summary>
    void docLibFileExits()
    {
        SPWeb currentSite = SPContext.Current.Web;
        SPDocumentLibrary docLib 
            = (SPDocumentLibrary)currentSite.GetList(currentSite.Url + "/Documents");

        //APPROACH 1
        if (docLib.RootFolder.Files[fileName] != null)
        {
            // do something 
            //This throws an Argument Exception
        }

        //APPROACH 2
        if (docLib.RootFolder.Files[fileName].Exists == true)
        {
            // do something 
            //Again this throws a Argument Exception
        }

        //APPROACH 3
        if (currentSite.GetFile(fileName).Exists == true)
        {
            // do something
            //work
        }

        //APPROACH 4
        bool fileExist = true;

        try { docLib.RootFolder.Files[fileName]; }
        catch (ArgumentException) { fileExist = false; }

        if (fileExists)
        {
            //...
        }

        

        //APPROACH 5
        SPSite oWebsite = SPContext.Current.Web;
        SPList docLib = oWebsite.Lists["docLib"] as SPDocumentLibrary;
        SPListItemCollection itemcolCVs = null;
        SPQuery oQueryFileCheck = new SPQuery();

        string FILENAME = ""; //FileName that you want to search.

        //You can use EQUALS or CONTAINS operation as per your requirement.
        //
        /*
        StringBuilder strBFileCheckQuery = new StringBuilder(
            "<Where>" +
                "<Eq>" +
                    "<FieldRef Name='FileLeafRef' />" +
                    "<Value Type='Text'>FILENAME</Value>" +
                "</Eq>" +
            "</Where>");
        */

        StringBuilder strBFileCheckQuery = new StringBuilder(
            "<Where>" +
                "<Contains>" +
                    "<FieldRef Name='FileLeafRef' />" +
                    "<Value Type='Text'>FILENAME</Value>" +
                "</Contains>" +
            "</Where>");

        oQueryFileCheck.Query = strBFileCheckQuery.ToString();
        if (docLib.GetItems(oQueryFileCheck).Count > 0)
        {
            //To do
        }
        
    }

P.S. Here CAML Query Builder helped me a lot to identify and build above SPQuery.

CAML Tips n Tricks --- Part 2

CAML --- Collaborative Application Markup Language

In continuation with my previous post ---
CAML Tips n Tricks

In this post I am going to discuss about CAML query for batch Update and Delete.

1) BATCH DELETE

    
    /// <summary>
    /// Get the CAML query for BATCH DELETION
    /// </summary>
    /// <param name="spList">SPList instance</param>
    /// <returns>SPQuery</returns>
    StringBuilder buildBatchDeleteCommand(SPList spList)
    {
        StringBuilder sbDelete = new StringBuilder();
        sbDelete.Append("<?xml version=\"1.0\" encoding=\"UTF-8\"?><Batch>");

        string command = "<Method>" +
                            "<SetList Scope=\"Request\">" + spList.ID + "</SetList>" +
                            "<SetVar Name=\"ID\">{0}</SetVar>" +
                            "<SetVar Name=\"Cmd\">Delete</SetVar>" +
                        "</Method>";

        foreach (SPListItem item in spList.Items)
        {
            sbDelete.Append(string.Format(command, item.ID.ToString()));
        }
        sbDelete.Append("</Batch>");
        return sbDelete;
    }

    /// <summary>
    /// Multiple records Deletion with SPQuery
    /// </summary>
    void BatchDelete(Object sender, EventArgs e)
    {
        //Get the SPQuery
        StringBuilder finalDeleteAllQuery = buildBatchDeleteCommand(oList);
        
        //Get the SPSite and Allow unsafe updates
        SPSite oWebsite = SPContext.Current.Web;
        oWebsite.AllowUnsafeUpdates = true;

        //Run the Batch command
        oWebsite.ProcessBatchData(finalDeleteAllQuery.ToString());

        //Disable unsafe updates
        oWebsite.AllowUnsafeUpdates = false;
    }    

2) BATCH UPDATE

    /// <summary>
    /// Get the CAML query for BATCH UPDATION
    /// Here building SPQuery to change "Final Status" column's value
    /// </summary>
    /// <param name="spList">SPList instance</param>
    /// <returns>SPQuery</returns>
    StringBuilder buildBatchUpdateCommand(SPList spList)
    {
        StringBuilder sbDelete = new StringBuilder();
        sbDelete.Append("<?xml version=\"1.0\" encoding=\"UTF-8\"?><Batch>");

        string command = "<Method>" +
                            "<SetList Scope=\"Request\">" + spList.ID + "</SetList>" +
                            "<SetVar Name=\"ID\">{0}</SetVar>" +
                            "<SetVar Name=\"Cmd\">Save</SetVar>" +
                            "<SetVar 
                                 Name=\"urn:schemas-microsoft-com:office:office
                                 #Final_x0020_Status\">{1}</SetVar>" +
                        "</Method>";

        //SPView specific SPListItems, you can skip following 3 lines 
        //and directly run foreach on SPList. 
        //E.g, foreach (SPListItem item in spList.Items)
        SPView spView = spList.Views["SPView_NAME"];
        SPViewFieldCollection collViewFields = spView.ViewFields;
        SPListItemCollection collItemsSrc = spList.GetItems(spView);

        foreach (SPListItem item in collItemsSrc)
        {
            sbDelete.Append(string.Format(command, item.ID.ToString(), "Completed"));
        }

        sbDelete.Append("</Batch>");
        return sbDelete;
    }

    /// <summary>
    /// Multiple records Update with SPQuery
    /// </summary>
    void BatchUpdate()
    {
        //Get the SPQuery
        StringBuilder finalUpdateAllQuery = buildBatchUpdateCommand(oList);
        
        //Get the SPSite and Allow unsafe updates
        SPSite oWebsite = SPContext.Current.Web;
        oWebsite.AllowUnsafeUpdates = true;

        //Run the Batch command
        oWebsite.ProcessBatchData(finalUpdateAllQuery.ToString());

        //Disable unsafe updates
        oWebsite.AllowUnsafeUpdates = false;
    }

Programmatically Export records from SPList to MS Excel

Programmatically export records from SPList to MS Excel in SharePoint.
What does above sentence mean???

Basically if you are a SharePoint developer OR user then you might know that we can do Import/Export between SPList and Microsoft Excel.
In this post I will discuss only about Export of records from SPList to MS Excel.
If you open a SharePoint's SPList, then in Action Toolbar, contains a link to open/export the SPList (in current applied SPView) in Excel Workbook and hence save it a Excel file (*.xls / *.iqv).

Now to achieve the above task programmatically we have to do some extra efforts:

1) Get the GUID of SPList - from where you want to export the records/SPListItem.

//SPList oList = ""; //Code to get the SPList

//Here I convert the GUID in Uppercase 
//and remove the special character hypen ('-') with required string.
string listGUID = oList.ID.ToString().ToUpper().Replace("-", "\u00252D");

2) Get the GUID of SPView - it can be default one (All Items) or custom SPView with required columns and settings like sorting, filter, etc.

//Here I convert the GUID in Uppercase 
//and remove the special character hypen ('-') with required string.
string viewGUID 
   = oList.Views["ExportRecords"].ID.ToString().ToUpper().Replace("-", "\u00252D");

3) Build the command, that will get executed on link's click.

//string spListName --- is SPList name. 
//I removed the special characters in that also.

//Here for readibility point of view I used string,
//you must use StringBuilder from performance point of view.
string strCommand = "javascript:EnsureSSImporter();"
                + "javaScript:ExportList('\u002f_vti_bin\u002fowssvr.dll?CS=65001\u0026"
                + "Using=_layouts\u002fquery.iqy\u0026"
                + "List=\u00257B" + listGUID + "\u00257D\u0026"
                + "View=\u00257B" + viewGUID + "\u00257D\u0026"
                + "RootFolder=\u00252FLists\u00252F" 
                + spListName.Replace("_", "\u00255F") + "\u0026"
                + "CacheControl=1')";

4) Consume/Call the above command via link's click.

<a id="linkExportData" onclick="<%=strCommand %>" 
      class="ms-sitetitle" style="font-size: 10px;">Export Records</a>

You can write the C# code of Step 1,2 and 3 in Page_Load event and HTML code of step 4 anywhere in you aspx page.

So when you click the "Export Records" link, it pop-up a dialog box to open the Records/SPList in Execl Workbook, that you can later on SAVE AS Excel file.

Once again IE Developer toolbar helped me to find the above solution/trick :)