WebPart in Sharepoint freezes after clicking a linkbutton - asp.net

Question

I have a user control inside a webpart inside sharepoint that I add some linkbuttons dynamically during runtime. each one when clicked is supposed to download a certain file from the database. however when one of those linkbuttons is clicked, this file is downloaded for once and then i can't click any other buttons or links or even the same one again on this user control and webpart. but i can still click other things outside the user control and webpart. do u have any idea? please tell me which part of the code i can add here if you need to check something. thank you :)
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using Microsoft.SharePoint;
using System.Collections.Generic;
using System.Drawing;
public class SearchResult : IComparable
{
private string __nID;
private string __sQuestion;
private string __sAnswer;
private string __nCategoryID;
private string __nPermission;
private string __nLastEdit;
private int __nOccurrence;
public SearchResult()
{
__nOccurrence = 0;
}
public string ID
{
get { return __nID; }
set { __nID = value; }
}
public string Quest
{
get { return __sQuestion; }
set { __sQuestion = value; }
}
public string Answer
{
get { return __sAnswer; }
set { __sAnswer = value; }
}
public string CategoryID
{
get { return __nCategoryID; }
set { __nCategoryID = value; }
}
public string Permission
{
get { return __nPermission; }
set { __nPermission = value; }
}
public string LastEdit
{
get { return __nLastEdit; }
set { __nLastEdit = value; }
}
public int Occurrence
{
get { return __nOccurrence; }
set { __nOccurrence = value; }
}
#region IComparable Members
public int CompareTo(SearchResult res)
{
if (this.Occurrence > res.Occurrence)
return -1;
if (this.Occurrence < res.Occurrence)
return 1;
return 0;
}
#endregion
#region IComparable Members
public int CompareTo(object obj)
{
SearchResult res = (SearchResult)obj;
if (this.Occurrence > res.Occurrence)
return -1;
if (this.Occurrence < res.Occurrence)
return 1;
return 0;
}
#endregion
}
[System.ComponentModel.Description("Questions")]
public partial class SampleProvider : System.Web.UI.UserControl, SmartPart.IConnectionProviderControl
{
const string FAQConnectionString = "";
private int FileID = 1;
private string CaregoryID = "1";
TextBox tbQuestion;
TextBox tbAnswer;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
ViewState["CategoryID"] = "0";
LoadTree();
}
System.Web.HttpContext context = System.Web.HttpContext.Current;
string username = context.User.Identity.Name;
LoadQuestions();
}
void LoadQuestions()
{
System.Data.SqlClient.SqlConnection con = new System.Data.SqlClient.SqlConnection();
con.ConnectionString = FAQConnectionString;
System.Data.SqlClient.SqlCommand com = new System.Data.SqlClient.SqlCommand();
com.Connection = con;
com.CommandText = "SELECT * FROM Questions";
System.Data.SqlClient.SqlDataReader dr;
con.Open();
dr = com.ExecuteReader();
PlaceHolderQuestions.Controls.Clear();
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/><br/><br/>"));
while (dr.Read())
{
if (ViewState["CategoryID"].ToString() != dr[3].ToString())
continue;
Label question = new Label();
question.Text = dr[1].ToString();
question.Font.Name = "Cambria";
question.Font.Bold = true;
question.Font.Size = 11;
question.Width = 500;
Label answer = new Label();
answer.Text = dr[2].ToString();
answer.Font.Name = "Cambria";
answer.Font.Size = 11;
answer.Width = 500;
LinkButton lnkbtnEdit = new LinkButton();
lnkbtnEdit.Click += new EventHandler(lnkbtnEdit_Click);
lnkbtnEdit.CommandArgument = dr[0].ToString();
lnkbtnEdit.CommandName = "edit";
lnkbtnEdit.Text = "Edit";
lnkbtnEdit.Font.Name = "Cambria";
lnkbtnEdit.Font.Size = 11;
lnkbtnEdit.Width = 50;
PlaceHolderQuestions.Controls.Add(question);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
PlaceHolderQuestions.Controls.Add(answer);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = FAQConnectionString;
System.Data.SqlClient.SqlCommand comm = new System.Data.SqlClient.SqlCommand();
comm.Connection = conn;
/////////////////////////// dr[2] for the QuestionID column at the question table
comm.CommandText = "SELECT * FROM Files WHERE QuestionID = " + dr[0].ToString();
System.Data.SqlClient.SqlDataReader drr;
conn.Open();
drr = comm.ExecuteReader();
while (drr.Read())
{
LinkButton lnkbtnDownloadFile = new LinkButton();
//name of the file ---> drr[2]
lnkbtnDownloadFile.Click += new EventHandler(lnkbtnDownloadFile_Click);
lnkbtnDownloadFile.Text = drr[2].ToString();
lnkbtnDownloadFile.CommandArgument = drr[2].ToString();
PlaceHolderQuestions.Controls.Add(lnkbtnDownloadFile);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
}
ShowLabels(dr[0].ToString());
conn.Close();
PlaceHolderQuestions.Controls.Add(lnkbtnEdit);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<p/>"));
}
con.Close();
}
void EditQuestion(string ID)
{
SqlConnection con = new SqlConnection();
con.ConnectionString = FAQConnectionString;
SqlCommand com = new SqlCommand("SELECT * FROM Questions WHERE ID = '" + ID + "'");
com.Connection = con;
SqlDataReader dr;
con.Open();
string quest="";
string answer = "";
string categoryID = "";
string lastEdit = "";
dr = com.ExecuteReader();
while (dr.Read())
{
quest = dr[1].ToString();
answer = dr[2].ToString();
categoryID = dr[3].ToString();
lastEdit = dr[5].ToString();
}
tbQuestion = new TextBox();
tbAnswer = new TextBox();
tbQuestion.TextMode = TextBoxMode.MultiLine;
tbAnswer.TextMode = TextBoxMode.MultiLine;
tbQuestion.Width = 360;
tbAnswer.Width = 360;
tbQuestion.Text = quest;
tbAnswer.Text = answer;
PlaceHolderQuestions.Controls.Clear();
PlaceHolderQuestions.Controls.Add(tbQuestion);
PlaceHolderQuestions.Controls.Add(tbAnswer);
SqlConnection conn = new SqlConnection();
conn.ConnectionString = FAQConnectionString;
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
/////////////////////////// dr[2] for the QuestionID column at the question table
comm.CommandText = "SELECT * FROM Files WHERE QuestionID = " + ID;
SqlDataReader drr;
conn.Open();
drr = comm.ExecuteReader();
PlaceHolder PlaceHolderFiles = new PlaceHolder();
PlaceHolderQuestions.Controls.Add(PlaceHolderFiles);
// for showing links to the files
while (drr.Read())
{
LinkButton lb = new LinkButton();
//name of the file ---> drr[2]
// lb.Click += new EventHandler(lb_Click);
lb.Text = drr[2].ToString();
PlaceHolderFiles.Controls.Add(lb);
LinkButton lnkbtnDelete = new LinkButton();
// lnkbtnDelete.Click+= new EventHandler(delete_Click);
lnkbtnDelete.CommandArgument = lb.Text;
lnkbtnDelete.Text = "Delete";
lnkbtnDelete.Width = 60;
lnkbtnDelete.Height = 25;
PlaceHolderFiles.Controls.Add(lnkbtnDelete);
PlaceHolderFiles.Controls.Add(new LiteralControl("<br/>"));
}
LinkButton lnkbtnSave = new LinkButton();
lnkbtnSave.Click += new EventHandler(lnkbtnSave_Click);
lnkbtnSave.Text = "Save";
PlaceHolderQuestions.Controls.Add(lnkbtnSave);
conn.Close();
}
void lnkbtnSave_Click(object sender, EventArgs e)
{
if (sender is LinkButton && (sender as LinkButton).CommandName == "save")
SaveQuestion((sender as LinkButton).CommandArgument);
}
private void UpdateQuestionByID(int questionID, string question, string answer, string lastEdited)
{
using (SqlConnection conn = new SqlConnection(FAQConnectionString))
{
conn.Open();
const string QUERY =
#"UPDATE Questions " +
#"SET Question = #Question, Answer = #Answer, LastEdit = #LastEdited " +
#"WHERE ID = #QuestionID";
using (SqlCommand cmd = new SqlCommand(QUERY, conn))
{
cmd.Parameters.AddWithValue("#Question", question);
cmd.Parameters.AddWithValue("#Answer", answer);
cmd.Parameters.AddWithValue("#LastEdited", lastEdited);
cmd.Parameters.AddWithValue("#QuestionID", questionID);
cmd.ExecuteNonQuery();
}
}
}
void SaveQuestion(string ID)
{
UpdateQuestionByID(int.Parse(ID), tbQuestion.Text, tbAnswer.Text, "a");
}
void lnkbtnEdit_Click(object sender, EventArgs e)
{
//if (sender is LinkButton && (sender as LinkButton).CommandName=="edit")
// EditQuestion((sender as LinkButton).CommandArgument);
string id = (sender as LinkButton).CommandArgument.ToString();
Response.Redirect("http://kermit:91/BIMS/Shared%20Documents/EditQuestion.aspx?k="+id);
ViewState["EditID"] = (sender as LinkButton).CommandArgument;
}
void lnkbtnDownloadFile_Click(object sender, EventArgs e)
{
if (sender is LinkButton)
DownloadFile((sender as LinkButton).CommandArgument);
}
private void DownloadFile(string fileName)
{
System.Data.SqlClient.SqlConnection con = new System.Data.SqlClient.SqlConnection();
con.ConnectionString = FAQConnectionString;
con.Open();
System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand();
cmd.Connection = con;
cmd.CommandText = "SELECT * FROM Files WHERE FileName = #ID";
cmd.Parameters.Add("#ID", System.Data.SqlDbType.NVarChar).Value = fileName;
System.Data.SqlClient.SqlDataReader sqlRead = cmd.ExecuteReader();
if (sqlRead.HasRows)
{
while (sqlRead.Read())
{
byte[] fileData = (byte[])sqlRead[3];
Response.Clear();
Response.AppendHeader("content-disposition", "attachment; filename=" + sqlRead[2]);
Response.ContentType = "application/octet-stream";
Response.BinaryWrite(fileData);
//Response.Flush();
//Response.End();
Response.Clear();
}
}
con.Close();
sqlRead.Close();
}
protected void lnkbtnAddQuestion_Click(object sender, EventArgs e)
{
}
private void LoadTree()
{
tvCategory.Nodes.Clear();
System.Data.SqlClient.SqlConnection con = new System.Data.SqlClient.SqlConnection();
con.ConnectionString = FAQConnectionString;
System.Data.SqlClient.SqlCommand com = new System.Data.SqlClient.SqlCommand();
com.Connection = con;
com.CommandText = "SELECT * FROM QuestionCategory WHERE ParentCategoryID = -1";
System.Data.SqlClient.SqlDataReader dr;
con.Open();
dr = com.ExecuteReader();
while (dr.Read())
{
TreeNode tn = new TreeNode();
tn.Text = dr[1].ToString();
tn.Value = dr[0].ToString();
tvCategory.Nodes.Add(tn);
AddChildren(tn);
}
con.Close();
}
private void AddChildren(TreeNode tn)
{
System.Data.SqlClient.SqlConnection con = new System.Data.SqlClient.SqlConnection();
con.ConnectionString = FAQConnectionString;
System.Data.SqlClient.SqlCommand com = new System.Data.SqlClient.SqlCommand();
com.Connection = con;
com.CommandText = "SELECT * FROM QuestionCategory WHERE ParentCategoryID = " + tn.Value;
System.Data.SqlClient.SqlDataReader dr;
con.Open();
dr = com.ExecuteReader();
while (dr.Read())
{
TreeNode ctn = new TreeNode();
ctn.Text = dr[1].ToString();
ctn.Value = dr[0].ToString();
tn.ChildNodes.Add(ctn);
AddChildren(ctn);
}
con.Close();
}
protected void tvCategory_SelectedNodeChanged(object sender, EventArgs e)
{
ViewState["CategoryID"] = tvCategory.SelectedValue;
// CaregoryID = tvCategory.SelectedValue;
LoadQuestions();
tvCategory.SelectedNode.Selected = false;
}
protected void btnSearch_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection();
con.ConnectionString = FAQConnectionString;
SqlDataAdapter adp = new SqlDataAdapter();
DataTable QuestionsTable = new DataTable();
using (SqlConnection oCn = new SqlConnection(FAQConnectionString))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM Questions", oCn);
cmd.CommandType = CommandType.Text;
adp.SelectCommand = cmd;
adp.Fill(QuestionsTable);
}
List<String> wordsSearched = new List<string>();
List<SearchResult> searchResults = new List<SearchResult>();
string[] words = txtbxSearch.Text.ToLower().Split();
//filtering the unnecessary words to prevent searching for
foreach (string s in words)
{
if (s == "to" || s == "the" || s == "is" || s == "are" || s == "in" || s == "of" || s == "on" || s == "with" || s == "are" || s == "it" || s == "this")
continue;
wordsSearched.Add(s);
}
//adding the search result and determine the frequency of occurrence
for (int i = 0; i < QuestionsTable.Rows.Count; i++)
foreach (string w in wordsSearched)
if (QuestionsTable.Rows[i][1].ToString().ToLower().IndexOf(w) > -1 || QuestionsTable.Rows[i][2].ToString().ToLower().IndexOf(w) > -1)
{
SearchResult result = new SearchResult();
result.ID = QuestionsTable.Rows[i][0].ToString();
result.Quest = QuestionsTable.Rows[i][1].ToString();
result.Answer = QuestionsTable.Rows[i][2].ToString();
result.CategoryID = QuestionsTable.Rows[i][3].ToString();
result.Permission = QuestionsTable.Rows[i][4].ToString();
result.LastEdit = QuestionsTable.Rows[i][5].ToString();
result.Occurrence++;
bool isFound = false;
for (int j = 0; j < searchResults.Count; j++)
if (searchResults[j].ID == result.ID)
{
searchResults[j].Occurrence++;
isFound = true;
break;
}
if (!isFound)
searchResults.Add(result);
}
SearchInTags(wordsSearched, searchResults);
searchResults.Sort();
//Session["SearchResults"] = searchResults;
//Response.Redirect("SearchResults.aspx");
LoadSearchResults(searchResults, wordsSearched);
}
void SearchInTags(List<string> words, List<SearchResult> searchResults)
{
foreach (string s in words)
{
using (SqlConnection con = new SqlConnection(FAQConnectionString))
{
con.Open();
SqlCommand cmd = new SqlCommand("SELECT * FROM Questions INNER JOIN QuestionKeyword ON Questions.ID=QuestionKeyword.QuestionID INNER JOIN Keywords ON QuestionKeyword.KeywordID=Keywords.ID WHERE Keywords.Keyword LIKE '%" + s + "%'", con);
SqlDataReader dr;
dr = cmd.ExecuteReader();
while (dr.Read())
{
SearchResult result = new SearchResult();
result.ID = dr[0].ToString();
result.Quest = dr[1].ToString();
result.Answer = dr[2].ToString();
result.CategoryID = dr[3].ToString();
result.Permission = dr[4].ToString();
result.LastEdit = dr[5].ToString();
result.Occurrence++;
bool isFound = false;
for (int j = 0; j < searchResults.Count; j++)
if (searchResults[j].ID == result.ID)
{
searchResults[j].Occurrence++;
isFound = true;
break;
}
if (!isFound)
searchResults.Add(result);
}
}
}
}
string[] ColorWords(string[] words, string color, List<string> selected)
{
for (int i = 0; i < words.Length; i++)
for(int j=0; j<selected.Count; j++)
if(words[i].ToLower()==selected[j].ToLower())
{
words[i] = "<span style='color: red;'>" + words[i] + "</span>";
break;
}
return words;
}
string ColorText(string text, List<string> selected)
{
int searchFrom = 0;
foreach (string s in selected)
{
int startIndex = text.ToLower().IndexOf(s, searchFrom);
if (startIndex < 0)
continue;
int length = s.Length;
text = text.Insert(startIndex, "<span style='color: red;'>");
text = text.Insert(startIndex + length + 26, "</span>");
}
return text;
}
void LoadSearchResults(List<SearchResult> searchResults, List<string> selected)
{
PlaceHolderQuestions.Controls.Clear();
foreach (SearchResult res in searchResults)
{
Label question = new Label();
question.Text = ColorText(res.Quest, selected);
question.Font.Name = "Cambria";
question.Font.Bold = true;
question.Font.Size = 11;
question.Width = 500;
Label answer = new Label();
answer.Text = ColorText(res.Answer, selected);
answer.Font.Name = "Cambria";
answer.Font.Size = 11;
answer.Width = 500;
HyperLink edit = new HyperLink();
string url = "http://kermit:91/BIMS/Shared%20Documents/EditQuestion.aspx?k=";
url += res.ID;
edit.NavigateUrl = url;
edit.Text = "Edit";
edit.Font.Name = "Cambria";
edit.Font.Size = 11;
edit.Width = 50;
PlaceHolderQuestions.Controls.Add(question);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
PlaceHolderQuestions.Controls.Add(answer);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
SqlConnection conn = new SqlConnection();
conn.ConnectionString = FAQConnectionString;
SqlCommand comm = new SqlCommand();
comm.Connection = conn;
/////////////////////////// dr[2] for the QuestionID column at the question table
comm.CommandText = "SELECT * FROM Files WHERE QuestionID = " + res.ID;
SqlDataReader drr;
conn.Open();
drr = comm.ExecuteReader();
while (drr.Read())
{
LinkButton lb = new LinkButton();
//name of the file ---> drr[2]
// lb.Click += new EventHandler(lb_Click);
lb.Text = drr[2].ToString();
PlaceHolderQuestions.Controls.Add(lb);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<br/>"));
}
ShowLabels(res.ID);
conn.Close();
PlaceHolderQuestions.Controls.Add(edit);
PlaceHolderQuestions.Controls.Add(new LiteralControl("<p/>"));
}
}
void ShowLabels(string questionID)
{
SqlConnection con = new SqlConnection(FAQConnectionString);
SqlCommand cmd = new SqlCommand();
cmd.CommandText = "SELECT * FROM QuestionKeyword INNER JOIN Keywords ON QuestionKeyword.KeyWordID=Keywords.ID WHERE QuestionID = " + questionID;
cmd.Connection = con;
SqlDataReader dr;
con.Open();
dr = cmd.ExecuteReader();
while (dr.Read())
{
Label lblKeyword = new Label();
lblKeyword.ForeColor = Color.Green;
lblKeyword.Text = dr[4].ToString();
PlaceHolderQuestions.Controls.Add(lblKeyword);
PlaceHolderQuestions.Controls.Add(new LiteralControl(" \t "));
}
con.Close();
PlaceHolderQuestions.Controls.Add(new LiteralControl("<p/>"));
}
#region IConnectionProviderControl Members
public object GetProviderData()
{
return null;
}
public string ProviderMenuLabel
{
get { return "Sends text data to"; }
}
#endregion
}
the weird thing that it works well when i put the same code in an asp.net page!!

Answer 1

Ahmad,
Check out the following link on the MSDN forums, as I believe the situation is similar (if not identical) to what you're describing:
http://social.msdn.microsoft.com/forums/en-US/sharepointdevelopment/thread/107b2c17-07fe-4a15-ad81-dcb31e1e9c84/
A couple of different approaches/solutions are discusssed.
I hope this helps!