/// <summary>
/// Asynchronously loads textual data from database.
/// </summary>
/// <param name="query">SQL query to the database</param>
/// <returns>Table of results returned from the database</returns>
public DataTable LoadDBTextAsync(string query)
{
DatabaseWorker dw = new DatabaseWorker();
DataTable t = dw.queryDBRows(query);
LoadCompleted(new LoadCompletedEventArgs(t, null, false, null));
return t;
}
/// <summary>
/// Loads images from database using asynchronous request processing.
/// </summary>
public void GetImagesAsync()
{
AsyncManager.Timeout = 10000;
ViewBag.Images = new ArrayList();
ViewBag.Tables = new ArrayList();
DatabaseWorker.connectDB();
DatabaseWorker dw = new DatabaseWorker();
for (int j = 0; j < 10; j++)
{
int count = dw.intQueryDB("select count(*) from Images");
for (int i = 1; i <= count; i++)
{
AsyncManager.OutstandingOperations.Increment();
AsyncWorker l = new AsyncWorker();
// Register the event handler to be notified when the async operation finishes
l.LoadDataCompleted += (sender, e) =>
{
// Place image contents in an array of images in viewbag
ViewBag.Images.Add("data:image/jpeg;base64," + @e.ImageContents);
AsyncManager.OutstandingOperations.Decrement();
};
// Execute async method (automatically on separate thread)
l.LoadDBImageAsync("select image from Images where imageID = " + i + " and exists (select * from ArticleAttachments where ImageID = " + i + ")");
}
}
DatabaseWorker.disconnectDB();
}
/// <summary>
/// Asynchronously loads binary data of an image from the database using the DatabaseWorker.
/// </summary>
/// <param name="query">SQL query to be sent to the database</param>
/// <returns>String representation of the binary data</returns>
public string LoadDBImageAsync(string query)
{
DatabaseWorker dw = new DatabaseWorker();
byte[] contents = dw.binaryQueryDB(query);
string base64string = Convert.ToBase64String(contents);
LoadCompleted(new LoadCompletedEventArgs(base64string, null, false, null));
return base64string;
}
/// <summary>
/// Loads images from database synchronously.
/// </summary>
/// <returns>View of images</returns>
public ActionResult GetImagesSynchronous()
{
DatabaseWorker dw = new DatabaseWorker();
DatabaseWorker.connectDB();
ViewBag.Images = new ArrayList();
ViewBag.Tables = new ArrayList();
for (int j = 0; j < 10; j++)
{
int count = dw.intQueryDB("select count(*) from Images");
for (int i = 1; i <= count; i++)
{
byte[] contents = dw.binaryQueryDB("select image from Images where imageID = " + i + " and exists (select * from ArticleAttachments where ImageID = " + i + ")");
// Place image contents in an array of images in viewbag
ViewBag.Images.Add("data:image/jpeg;base64," + Convert.ToBase64String(contents));
}
}
DatabaseWorker.disconnectDB();
ViewBag.Title = "Synchronous Test Loading Media From Database";
return View("RegularQueries");
}
/// <summary>
/// Loads images from database synchronously.
/// </summary>
/// <returns>View of textual tables</returns>
public ActionResult GetTextSynchronous()
{
DatabaseWorker dw = new DatabaseWorker();
DatabaseWorker.connectDB();
ViewBag.Tables = new ArrayList();
ViewBag.Images = new ArrayList();
String[] tableNames = { "Technology", "Music", "Nature", "Health", "Sports", "Business" };
for (int j = 0; j < tableNames.Length; j++)
{
AsyncWorker aw = new AsyncWorker();
DataTable table = aw.LoadDBTextAsync("select DocumentTitle as Title, Username, FirstName, LastName " +
"from Articles, Groups, SiteUsers where Articles.GroupID=Groups.GroupID and SiteUsers.UserID=Articles.UserID "
+ "and GroupName = '" + tableNames[j] + "' order by FirstName, LastName ASC");
table.TableName = tableNames[j] + " Articles:";
ViewBag.Tables.Add(table);
}
DatabaseWorker.disconnectDB();
ViewBag.Title = "Synchronous Test Loading Text From Database";
return View("RegularQueries");
}
public ActionResult GetTextCache()
{
DatabaseWorker dw = new DatabaseWorker();
DatabaseWorker.connectDB();
ViewBag.Tables = new ArrayList();
ViewBag.Images = new ArrayList();
String[] tableNames = { "Technology", "Music", "Nature", "Health", "Sports", "Business" };
for (int j = 0; j < tableNames.Length; j++)
{
AsyncWorker aw = new AsyncWorker();
DataTable table;
object t = HttpRuntime.Cache.Get(tableNames[j]);
if (t == null)
{
table = aw.LoadDBTextAsync("select DocumentTitle as Title, Username, FirstName, LastName from Articles, Groups, SiteUsers " +
"where Articles.GroupID=Groups.GroupID and SiteUsers.UserID=Articles.UserID and GroupName = '"+tableNames[j]+"'" +
" order by FirstName, LastName ASC");
table.TableName = tableNames[j] + " Articles:";
HttpRuntime.Cache.Insert(tableNames[j], table, null, System.Web.Caching.Cache.NoAbsoluteExpiration, new TimeSpan(0, 1, 0));
}
else
{
table = (DataTable)t;
}
ViewBag.Tables.Add(table);
}
DatabaseWorker.disconnectDB();
ViewBag.Title = "Caching Test Loading Text From Database";
return View("RegularQueries");
}
/// <summary>
/// Loads images from database using asynchronous method calling.
/// </summary>
public void GetTextAsync()
{
AsyncManager.Timeout = 10000;
ViewBag.Images = new ArrayList();
DatabaseWorker.connectDB();
DatabaseWorker dw = new DatabaseWorker();
ViewBag.Tables = new ArrayList();
String[] tableNames = { "Technology", "Music", "Nature", "Health", "Sports", "Business" };
for (int j = 0; j < tableNames.Length; j++)
{
AsyncManager.OutstandingOperations.Increment();
AsyncWorker l = new AsyncWorker();
l.LoadDataCompleted += (sender, e) =>
{
e.Data.TableName = tableNames[j] +" Articles:";
ViewBag.Tables.Add(e.Data);
AsyncManager.OutstandingOperations.Decrement();
};
l.LoadDBTextAsync("select DocumentTitle as Title, Username, FirstName, LastName from Articles, Groups, SiteUsers " +
"where Articles.GroupID=Groups.GroupID and SiteUsers.UserID=Articles.UserID and GroupName = '"+tableNames[j]+"'" +
" order by FirstName, LastName ASC");
}
DatabaseWorker.disconnectDB();
}
public ActionResult GetMediaCache()
{
DatabaseWorker dw = new DatabaseWorker();
DatabaseWorker.connectDB();
ViewBag.Tables = new ArrayList();
ViewBag.Images = new ArrayList();
for (int j = 0; j < 10; j++)
{
int count = dw.intQueryDB("select count(*) from Images");
for (int i = 1; i <= count; i++)
{
byte[] contents;
object cached = HttpRuntime.Cache.Get("DB.Images." + i);
if (cached == null)
{
contents = dw.binaryQueryDB("select image from Images where imageID = " + i + " and exists (select * from ArticleAttachments where ImageID = " + i + ")");
HttpRuntime.Cache.Insert("DB.Images." + i, contents, null, System.Web.Caching.Cache.NoAbsoluteExpiration, new TimeSpan(0, 1, 0));
}
else
{
contents = (byte[])cached;
}
ViewBag.Images.Add("data:image/jpeg;base64," + Convert.ToBase64String(contents));
}
}
DatabaseWorker.disconnectDB();
ViewBag.Title = "Caching Test Loading Media From Database";
return View("RegularQueries");
}
