C# - Can Use HashTable For Temporary Data Storage After Reading Data From Database
Feb 5, 2010
I am looking for opinions and best coding practices.I need to get info from a database with a query such as SELECT this, that FROM MyDB (returning 2 fields). Would it be wrong to use a hashtable for temporary storage?Is there a better way to accomplish the same thing? What about if I am returning more than 2 fields, would it be best to step up to a DataSet or something?
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
GetData();
[code]...
I need to do edit funtionality for registration forms (5 in number) in a trading system. Requirment is to do it in a way that user edit details in a form and click next or previous button and data will be saved somewhere until user reach last form and click save button. On this click all changes will be updated to database table. where I should hold this temporary data ? I cant use database tables for this. There come many options in mind like cach, session and application variables. But I am confuse which way will best performance wise. There are 5 forms and every form has 15 to 25 fields in it. I dont know expected no of users but hoping a good count.
I have defined a public static HashTable. It stores data for a few seconds of runtime, and then data disappears, and then the HashTable becomes null.What is the issue and how do I solve it?
L server into one datatable inside DBLayer.I want to return this table as Hashtable inside BLL, and I want to show the result inside GridView inside Presentation Layer.
I have a requirement in which i have a database table which has 4 columns Id,Name,position,city.....now i have a form in which the user will be filling in the id and then the other three columns should auto populate ....now i want a web service which will make a data connection and get the Id from the form and then query the database and get the other three columns..i am pretty new to web services ..can somebody give me some heads up on how to achieve this...let me know if i have to provide more details.
I have the following data that basically I only need a few bits of information from:
Resource:X - Y;Z - Å;Type:(all) From Date: 07/12/2010 - To Date 07/12/2010 Sort by:Time Include Referring source/physician:No Footer:Default Criteria:None ","Appointments","X, Y","ZAssociates","Monday, July 12, 2010","Time","Patient Name","Patient ID","Appt. Type","Ref. Source/ Physician","Phone","Type","DOB ","Z, X","Y","7/12/2010 12:00:00AM","Time","Patient Name","Patient ID","Appt. Type","Phone","Type","DOB "," 7:30 [snip]
The only things I need from this are:
Patients Name Drs Name Patients Phone Number Appt Time Appt Date
and the rest of the information I can discard. A customer uploads this as a .csv file (even though it really isn't as you can see) and I'd like to parse the needed information and post that to my SQL database and discard the rest. I think I can do this with a dataset but I've never built that before. The fields from the customer will always be the same and the fields I will need will always be the same. Also, the date time has to be in the format of yyyy/mm/dd:hhmm and the phone number always has to have 512 as a prefix. Here is the code I currently have for my site:
Imports System.IO Imports System.Data Imports System.Data.SqlClient Partial Class _Default Inherits System.Web.UI.Page Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load End Sub Protected Sub Submit1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Dim SaveLocation = "\xxxWEB3wwwrootWebfile1RemindersDoug_Ancildoug.csv" If UploadFile(SaveLocation) Then 'the file was uploaded: now try saving it to the database SaveToDatabase(SaveLocation) End If End Sub Private Function UploadFile(ByVal SavePath As String) As Boolean Dim fileWasUploaded As Boolean = False 'indicates whether or not the file was uploaded 'Checking if the file upload control contains a file If Not File1.PostedFile Is Nothing And File1.PostedFile.ContentLength > 0 Then Try 'checking if it was .txt file BEFORE UPLOADING IT! 'You used to upload it first...but the file could be a virus If File1.FileName = ("doug.csv") = False Then 'The file is not the expected type...do not upload it 'just post the validation message message.Text = "Sorry, thats not the correct file." message2.Text = "Please locate and upload 'doug.csv'" Else 'The file is a .txt file 'checking to see if the file exists already 'If it does exist Deleting the existing one so that the new one can be created If IO.File.Exists(SavePath) Then IO.File.Delete(SavePath) End If 'Now upload the file (save it to your server) File1.PostedFile.SaveAs(SavePath) 'After saving it check to see if it exists If File.Exists(SavePath) Then 'Upload was sucessful message.Text = "Thank you for your submission." fileWasUploaded = True Else 'the file was not saved message.Text = "Unable to save the file." End If End If Catch Exc As Exception 'We encountered a problem message.Text = "Your file was not in the correct format. Please contact Customer Service at xxxx-xxxx-xxxx." End Try Else 'No file was selected for uploading message.Text = "Please select a file to upload." End If Return fileWasUploaded End Function Private Sub SaveToDatabase(ByVal SavePath As String) Try Dim sqlQueryText As String = _ "BULK INSERT dialerresults " + _ "FROM '" & SavePath & "' " + _ "WITH ( FIELDTERMINATOR = ',' , ROWTERMINATOR = ' ' )" ' and bulk import the data: 'If ConfigurationManager.ConnectionStrings("Dialerresults") IsNot Nothing Then 'Dim connection As String = ConfigurationManager.ConnectionStrings("Dialerresults").ConnectionString Dim connection As String = "data source=10.2.1.40;initial catalog=IVRDialer;uid=xxxx;password=xxxxx;" Using con As New SqlConnection(connection) con.Open() ' execute the bulk import Using cmd As New SqlCommand(sqlQueryText, con) cmd.ExecuteNonQuery() End Using End Using 'Else 'message.Text="ConfigurationManager.ConnectionStrings('Dialerresults') is Nothing!" 'End If Catch ex As Exception message.Text = "Your file was not in the correct format. Please contact Customer Service at xxxxxxx." End Try End Sub End Class
1. I know about collections but I dont remember the precess. I know you drag a sqldatasource control on the form(Select everything in the database ie. selct *) and then delete it. But how do I use it i code.
Example. I need to select services where country=canada from the Agencies table.
2. I know how to manually pull data from an access database using the code below. I want to know how to pull data from a sql database just like the one below.
3. explain the difference between Collections and manually pulling it like the one bellow?
i'm retreiving data(API) with JSON format and i'm parsing it inside a hashtable,it seems like some specific keys have a value= hashtable(or arraylist!)below is how i'm extractin the the first layer value
[Code]....
the problem is where the values are equal to arraylist i'm not able to extract themIs there any way to extract the second layer keys and values?<i> (btw i'm very new to hashtables and arraylists)</i>
1 GridView ( For Temporary Data Holding of above controls )
Now what i want is that when a user fills some data in textboxes and select something from dropdown , then clicks on Add Row , this temporary gridview shows that data in it ....
I have one parent gridview where each record will link to its details page (another child gridview in modal popup). May I know how do I store the values of the child gridview temporary (maybe in session) and repopulate the data into the parent gridview? Current problem is: once I click save in the child modalpop gridview, it binds the parent gridview before the child gridview data is stored in session. I want to store the data temporary until user click save in the parent gridview.
I have data for Visa, Mastercard, moneybookers, etc. .. How do you propose to store data? In each table separately or not? You might like: 1 table that stores all the data and then call the information according to Visa, Mastercard, moneybookers, etc. Example: a table stored all data has deposit_options from each payment, or payments for each option do I need to each payment separately.
I'm thinking of using 3 layered architecture in my web site.Kind of classic layers - Presentation, BL, DAL and BO - business objects, just like in this great article http://imar.spaanjaars.com/QuickDocId.aspx?quickdoc=416I will have 4 projects according to levels.I'm goung to store data in xml files and my question is where should those files be located? In App_Data folder of web site? Then how DAL will know path where to find files to parse?
On a website such as Amazon, they usually have a prodcut description which is normally 2 - 3 paragraphs of description. Would these information be stored on a database, or would they use include files for those sections, would it be stored in an XML file? I have a website which stores everything in a database and for most of it the website works. EG, in my database, I have a table with Column Names such as ISBN Number, Book Name, Publisher Name and all of which don't go above 50 characters! In some cases, the descriptions go on and on over several paragraphs. Where should this be stored? In the table or in another location which the database references?
I'm starting to learn MVC 2.0 and I'm trying to create a site with a quiz: user is asked a question and given several options of answer. If he chooses the right answer he gets some points, if he doesn't, he looses them.
I tried to do this the following way
public class HomeController : Controller { private ITaskGenerator taskGenerator = new TaskGenerator(); private string correctAnswer;
[Code]....
But I have a problem: when user answers the cotroller class is recreated and I loose correct answer. So what is the best place to store correct answer? Should I create a static class for this purpose?
