I have tried to sort the list in many ways, but none work for me. I must be doing something wrong. I want to sort the List details then serialize it and send it to the UI, so that i have a sorted List in the UI.
So basically i want Return strJson to return the sorted(sorted by the sort property) List. Hope i am making sense.
<WebMethod(Description:="Get Home Page Items Page Wise", EnableSession:=True)> _
<ScriptMethod(ResponseFormat:=ResponseFormat.Json)>
Public Function GetHomePageItemsPageWise(ByVal pageIndex As String) As Object
Dim details As New List(Of HomePageObject)()
Dim idObject As New List(Of GetIdBasedOnInterest)()
idObject = CType(BLL.GetDataByInterests(CType(BLL.GetAccIdFromSocialAuthSession(), Integer)), List(Of GetIdBasedOnInterest))
Dim cmd As DbCommand = _db.GetStoredProcCommand("GetHomePageObjectPageWise")
_db.AddInParameter(cmd, "PageIndex", SqlDbType.VarChar, pageIndex)
_db.AddInParameter(cmd, "PageSize", SqlDbType.Int, 10)
_db.AddOutParameter(cmd, "PageCount", SqlDbType.Int, 1)
_db.AddInParameter(cmd, "whereStoryID", SqlDbType.VarChar, idObject(0).StoryIds)
_db.AddInParameter(cmd, "whereAlbumID", SqlDbType.VarChar, idObject(0).AlbumIds)
_db.AddInParameter(cmd, "wherePictureID", SqlDbType.VarChar, idObject(0).PictureIds)
Try
Using ds As DataSet = _db.ExecuteDataSet(cmd)
For Each rs As DataRow In ds.Tables(0).Rows
Dim homePageObject As New HomePageObject()
homePageObject.AlbumId = rs("AlbumId").ToString()
homePageObject.StoryTitle = rs("StoryTitle").ToString()
homePageObject.AlbumName = rs("AlbumName").ToString()
homePageObject.AlbumCover = rs("AlbumCover").ToString()
homePageObject.Votes = rs("Votes").ToString()
homePageObject.PictureId = rs("PictureId").ToString()
homePageObject.TableName = rs("tableName").ToString()
homePageObject.PageCount = CType(cmd.Parameters("#PageCount").Value, Integer)
homePageObject.Sort = Guid.NewGuid()
details.Add(homePageObject)
Next
End Using
Catch ex As Exception
MsgBox(ex.Message)
End Try
Dim js As New JavaScriptSerializer()
Dim strJson As String = js.Serialize(details.ToArray)
Return strJson
End Function
To randomize the list you can do the following. (And you do not need the Sort property in HomePageObject to accomplish this)
Dim rnd As new Random()
Dim strJson As String = js.Serialize(details.OrderBy(Function(x) rnd.Next()).ToArray())
Related
I'm trying to follow a simple example (link below) to learn Web API and am unable to get it list all records from my underlying table. The following will only list the last record in the table when making the api call.
<HttpGet>
Public Function GetEmployees() As Employee
Dim reader As SqlDataReader = Nothing
Dim myConnection As SqlConnection = New SqlConnection()
myConnection.ConnectionString = "myconnectionstring"
Dim sqlCmd As SqlCommand = New SqlCommand()
sqlCmd.CommandType = CommandType.Text
sqlCmd.CommandText = "Select * from tblEmployee"
sqlCmd.Connection = myConnection
myConnection.Open()
reader = sqlCmd.ExecuteReader()
Dim emp As Employee = Nothing
While reader.Read()
emp = New Employee()
emp.EmployeeId = Convert.ToInt32(reader.GetValue(0))
emp.Name = reader.GetValue(1).ToString()
emp.ManagerId = Convert.ToInt32(reader.GetValue(2))
End While
Return emp
myConnection.Close()
End Function
I've tried changing the function type to the following but get the error "Unable to cast object of type 'Employee' to type 'System.Collections.Generic.IEnumerable"
Public Function GetEmployees() As IEnumerable(Of Employee)
Credit to original tutorial:
http://www.c-sharpcorner.com/UploadFile/97fc7a/webapi-restful-operations-in-webapi-using-ado-net-objects-a/
In the code you provided, you're creating a single a variable "emp" of type "Employee". Your "While" loop executes and keeps resetting the "emp" variable on each iteration. Instead of using a single variable, you need a collection of Employees --
Public Function GetEmployees() As List(Of Employee)
Dim reader As SqlDataReader = Nothing
Dim myConnection As SqlConnection = New SqlConnection()
myConnection.ConnectionString = "myconnectionstring"
Dim sqlCmd As SqlCommand = New SqlCommand()
sqlCmd.CommandType = CommandType.Text
sqlCmd.CommandText = "Select * from tblEmployee"
sqlCmd.Connection = myConnection
myConnection.Open()
reader = sqlCmd.ExecuteReader()
Dim empList As New List(Of Employee)()
While reader.Read()
Dim emp As Employee = New Employee()
emp.EmployeeId = Convert.ToInt32(reader.GetValue(0))
emp.Name = reader.GetValue(1).ToString()
emp.ManagerId = Convert.ToInt32(reader.GetValue(2))
empList.Add(emp)
End While
myConnection.Close()
Return empList
End Function
To sum up the changes --
Function should return a List of Employee instead of a single Employee object
Create a new Employee on every loop, populate it, then add it to the list
Close your connection before returning
Return the list
I having trouble passing back the result which is multiple row getting from MS-SQL2012 to client. I have tried to google up but still not find the solution. Since I'm new in .NET and this is my first webservice, required an assistant to solve my problem or suggest any better solution.
Result need to pass back to client
Public Class Service1
Inherits System.Web.Services.WebService
Public Class Dealer
Public IDNo, ICFound, POFound As String
End Class
<WebMethod()> _
Public Function DailyCheckDealer(records As String()()) As String
Dim mylist As List(Of String()) = records.ToList()
Dim datarow As String = ""
Dim result As String = "Done"
For i As Integer = 0 To mylist.Count - 1
Dim m As String() = mylist(i)
For j As Integer = 0 To m.Length - 1
datarow += m(j) + " "
Next
Next
//Insert the array into the database.
Dim objDealer As New Dealer
Dim myConnString = System.Configuration.ConfigurationManager.AppSettings("MM_CONNECTION_STRING_iPRIS")
Dim myConnection1 = New SqlConnection(myConnString)
Dim myCommand = New SqlCommand()
myCommand.CommandType = CommandType.StoredProcedure
myCommand.Connection = myConnection1
myCommand.CommandText = "DailyCheckDealer"
myCommand.Parameters.Add("#DataRow", SqlDbType.VarChar, 8000).Value = datarow
myConnection1.Open()
myCommand.ExecuteNonQuery()
myConnection1.Close()
// Get the record(s) after processing and return it back to client
Dim myConnection2 = New SqlConnection(myConnString)
Dim objComm As New SqlCommand("Select IDNo, IDFound, POFound From DailyDealerCheck Order By IDNo", myConnection2)
myConnection2.Open()
Dim sdr As SqlDataReader = objComm.ExecuteReader()
If sdr.Read() Then
objDealer.IDNo = sdr("IDNo").ToString()
objDealer.ICFound = sdr("IDFound").ToString()
objDealer.POFound = sdr("POFound").ToString()
End If
myConnection2.Close()
Return objDealer
End Function
End Class
You're getting your data and putting it into objDealer which is an instance of type Dealer. You then actually have Return objDealer
Clrearly you want to return an instance of Dealer. However your function is declared as returning a string. That shouldn't even compile! Change the declaration to this:
<WebMethod()> _
Public Function DailyCheckDealer(records As String()()) As Dealer
That will allow it to return a Dealer not a string.
EDIT - to return more than one Dealer:
<WebMethod()> _
Public Function DailyCheckDealer(records As String()()) As List(Of Dealer)
' code left out
Dim myConnection2 = New SqlConnection(myConnString)
Dim objComm As New SqlCommand("Select IDNo, IDFound, POFound From DailyDealerCheck Order By IDNo", myConnection2)
' Create list of Dealers for return
Dim dealerList as New List(Of Dealer)
myConnection2.Open()
Dim sdr As SqlDataReader = objComm.ExecuteReader()
If sdr.Read() Then
objDealer.IDNo = sdr("IDNo").ToString()
objDealer.ICFound = sdr("IDFound").ToString()
objDealer.POFound = sdr("POFound").ToString()
' Add the latest to the list
dealerList.Add(objDealer)
End If
myConnection2.Close()
' Return list of dealers
Return dealerList
End Function
Its my handler (.ashx)
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else Throw New ArgumentException("No parameter specified") End If
Dim imageData() As Byte = {}
' get the image data from the database using the employeeId Querystring context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(imageData)
Everything is working fine.Only the imageData length is 0 so the image is unable to display.
#Sean: its elsewhr.. here the querystring correctly takes the employeeid passed...
heres the code for db access:
Public Sub bind()
Dim ds1 As New DataSet()
Dim con As New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("ConnectionString").ToString)
con.Open()
Dim query As String = "select * from EmployeeTable"
Dim cmd As New SqlCommand()
Dim da1 As New SqlDataAdapter(query, con)
da1.Fill(ds1, "EmployeeTable")
GridView1.DataSource = ds1.Tables("EmployeeTable")
GridView1.DataBind()
con.Close()
End Sub
You're loading a load of data into the GridView but nothing is being loaded into your imageData variable. So we'll just connect to the database and pull that data out. I'm assuming your image column is called imageData but please change as appropriate.
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then
EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else
Throw New ArgumentException("No parameter specified")
End If
Dim imageData() As Byte = {}
' get the image data from the database using the employeeId Querystring
Using con As New SqlConnection(ConfigurationManager.AppSettings("ConnectionString"))
Using cmd As New SqlCommand("SELECT imageData FROM EmployeeTable WHERE EmployeeID = #EmployeeID", con) 'select imageData column, change column name as appropriate
cmd.Parameters.AddWithValue("#EmployeeID", EmployeeID)
Try
con.Open()
Using rdr As SqlDataReader = cmd.ExecuteReader()
If rdr.Read() Then
imageData = CType(rdr("imageData"), Byte()) 'convert imageData column from result set to byte array and assign to variable
End If
End Using
Catch ex As Exception
'do any error handling here
End Try
End Using
End Using
context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(imageData)
Changed the code in the handler to this:
Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then
EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else
Throw New ArgumentException("No parameter specified")
End If
Dim Image() As Byte = {}
' get the image data from the database using the employeeId Querystring
Dim con As New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("ConnectionString").ToString)
Dim cmd As New SqlCommand("SELECT Image FROM EmployeeTable WHERE EmployeeID = #EmployeeID", con)
'select imageData column, change column name as appropriate
cmd.Parameters.AddWithValue("#EmployeeID", EmployeeID)
Try
con.Open()
Dim rdr As SqlDataReader = cmd.ExecuteReader()
While rdr.Read()
Image = CType(rdr("Image"), Byte())
'convert imageData column from result set to byte array and assign to variable
End While
Catch ex As Exception
'do any error handling here
End Try
context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(Image)
End Sub
Worked for me, may be it will work for you too...
Here is whats happening , If the user is logged in - this is called directly from Page_Load
Protected Sub EnterNewTransInDb()
Dim conn As New SqlConnection(ConfigurationManager.ConnectionStrings("connstring").ConnectionString)
Dim comm As New SqlCommand("INSERT INTO tblRegisterRedirect (RegID , UserID, EventID, TimeStamp) VALUES (#RegID, #UserID, #EventID , getdate()) ;", conn)
Dim RegID As Guid
RegID = Guid.NewGuid()
Dim GIUDuserid As Guid
GIUDuserid = New Guid(HttpContext.Current.Request.Cookies("UserID").Value.ToString())
Dim GIUDevnetid As New Guid(HttpContext.Current.Request.QueryString("id").ToString())
comm.Parameters.AddWithValue("#RegID", RegID)
comm.Parameters.AddWithValue("#UserID", GIUDuserid)
comm.Parameters.AddWithValue("#EventID", GIUDevnetid)
Try
conn.Open()
Dim i As Integer = comm.ExecuteNonQuery()
conn.Close()
Catch ex As Exception
Dim errors As String = ex.ToString()
End Try
Dim URL As String = Request.QueryString("url").ToString()
Response.Redirect(URL + "?aid=854&rid=" + RegID.ToString())
End Sub
This works great, but if their not logged in , then they enter their log-in credentials - this happens on Button_Click event, in the click event I call this function EnterNewTransInDb() , When I run it this time , after logging in - SAME CODE , it throws an exception - Object reference is null - referring to the querystring
Protected Sub btnLogin_Click(sender As Object, e As System.EventArgs) Handles btnLogin.Click
'took out code SqlConnection onnection and SqlDataReader Code
dbCon.Open()
'If Email and PW are found
If dr.Read Then
Dim appCookie As New HttpCookie("UserID")
appCookie.Value = dr("GUID").ToString()
appCookie.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie)
Dim appCookie1 As New HttpCookie("UserName")
appCookie1.Value = dr("UserName").ToString
appCookie1.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie1)
Dim appCookie2 As New HttpCookie("UserEmail")
appCookie2.Value = txtEmail.Text.ToLower()
appCookie2.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie2)
Dim appCookie3 As New HttpCookie("Lat")
appCookie3.Value = dr("GeoLat").ToString()
appCookie3.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie3)
Dim appCookie4 As New HttpCookie("Long")
appCookie4.Value = dr("GeoLong").ToString()
appCookie4.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie4)
Dim appCookie5 As New HttpCookie("City")
appCookie5.Value = dr("City").ToString()
appCookie5.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie5)
Dim appCookie6 As New HttpCookie("State")
appCookie6.Value = dr("State").ToString
appCookie6.Expires = DateTime.Now.AddDays(30)
HttpContext.Current.Response.Cookies.Add(appCookie6)
HttpContext.Current.Response.Cookies("EO_Login").Expires = Now.AddDays(30)
HttpContext.Current.Response.Cookies("EO_Login")("EMail") = txtEmail.Text.ToLower()
Dim sUserData As String = HttpContext.Current.Server.HtmlEncode(HttpContext.Current.Request.Cookies("UserID").Value) & "|" & HttpContext.Current.Server.HtmlEncode(HttpContext.Current.Request.Cookies("UserName").Value) & "|" & HttpContext.Current.Server.HtmlEncode(HttpContext.Current.Request.Cookies("UserEmail").Value)
' Dim sUserData As String = "dbcf586f-82ac-4aef-8cd0-0809d20c70db|scott selby|scottselby#live.com"
Dim fat As FormsAuthenticationTicket = New FormsAuthenticationTicket(1, _
dr("UserName").ToString, DateTime.Now, _
DateTime.Now.AddDays(6), True, sUserData, _
FormsAuthentication.FormsCookiePath)
Dim encTicket As String = FormsAuthentication.Encrypt(fat)
HttpContext.Current.Response.Cookies.Add(New HttpCookie(FormsAuthentication.FormsCookieName, encTicket))
'If Email and Pw are not found
Else
dr.Close()
dbCon.Close()
End If
'Always do this
dr.Close()
sSql = "UPDATE eo_Users SET LastLogin=GETUTCDATE() WHERE GUID=#GUID; "
cmd = New SqlCommand(sSql, dbCon)
cmd.Parameters.AddWithValue("#GUID", HttpContext.Current.Session("UserID"))
cmd.ExecuteNonQuery()
dbCon.Close()
EnterNewTransInDb()
'Dim URL As String = Request.QueryString("url").ToString()
'Response.Redirect(URL + "?aid=854&rid=" + RegID.ToString())
End Sub
Assuming you only want this code to run if there is a valid QueryString, you could put a guard clause at the beginning of the method to simply check if QueryString is null and then perform some other action if this page is called without a QueryString.
Try setting the breakpoints before the call and make sure the variables are assigned values.
Have you tried putting a breakpoint on Dim URL As String = Request.QueryString("url").ToString() line in your code? Maybe you just need to evaluate first the querystring for the 'url' parameter, if it exists; before converting it to a string.
I am using below mentioned Ado.net function and resultset bind with grid view, however I am getting the duplicate rows in the resultset.
Please help me out.
Thanks
Private _products As New List(Of Product)
Public Property Products As List(Of BusinessObjects.Product)
Get
Return _products
End Get
Set(ByVal value As List(Of BusinessObjects.Product))
_products = value
End Set
End Property
Public Function GetProductDetails() As List(Of Product)
Dim product As New BusinessObjects.Product
Using connection As New SqlConnection
connection.ConnectionString = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
connection.Open()
Using Command As New SqlCommand("select * from T_product", connection)
Dim rdr As SqlDataReader
rdr = Command.ExecuteReader
While rdr.Read()
product.ProductID = rdr("ProductID")
product.ProductName = rdr("ProductName")
Products.Add(product)
End While
GridView1.DataSource = Products
GridView1.DataBind()
End Using
End Using
Return Products
End Function
You should make Dim product As New BusinessObjects.Product initialization inside while reading from SqlDataReader instance
Set(ByVal value As List(Of BusinessObjects.Product))
_products = value
End Set
End Property
Public Function GetProductDetails() As List(Of Product)
Using connection As New SqlConnection
connection.ConnectionString = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
connection.Open()
Using Command As New SqlCommand("select * from T_product", connection)
Dim rdr As SqlDataReader
rdr = Command.ExecuteReader
While rdr.Read()
Dim product As New BusinessObjects.Product
product.ProductID = rdr("ProductID")
product.ProductName = rdr("ProductName")
Products.Add(product)
End While
GridView1.DataSource = Products
GridView1.DataBind()
End Using
End Using
Return Products
End Function
The problem is you are updating and adding same product every time. Create product object inside the While loop as below.
Public Function GetProductDetails() As List(Of Product)
Using connection As New SqlConnection
connection.ConnectionString = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
connection.Open()
Using Command As New SqlCommand("select * from T_product", connection)
Dim rdr As SqlDataReader
rdr = Command.ExecuteReader
While rdr.Read()
Dim product As New BusinessObjects.Product ' product object create here
product.ProductID = rdr("ProductID")
product.ProductName = rdr("ProductName")
Products.Add(product)
End While
GridView1.DataSource = Products
GridView1.DataBind()
End Using
End Using
Return Prod