How do you do nested recordset loops in ADO.NET? In ADO, you could just open one firehose cursor for the outer loop and a static, client-side, read-only cursor for the inner loop and nest the loops. But you can only open one DataReader at a time and Datasets aren't read-only.
'Classic ADO Code
Dim rsOuter as New ADODB.Recordset
Dim rsInner as New ADODB.Recordset
[code]....
how to create this sequence using a for loop and/or nested for loops?
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[Code].....
I'd like to be able to do something like this:
Dim newdata(,) As String = New String(,) { _
{"foo", "bar"}, _
{"fum", "baz"} _
[code]....
If I change the outer loop to:
For Each str() As String In newdata
It builds ok but I don't get what I want. The outer loop process the elements of newdata as a 1d array and the inner loop sees each character of the strings from the outer loop.So...is there a way to use the for each structure and process a 2d string array? If so, what should I change? If not, what is the best alternative?
I am trying to write a program that using a nested do while loop and If/If Else statement to draw a shape, and also using a nested do until and If/ElseIf statement to draw another shape.
View 18 RepliesToday is not one of those days. I know there is an elegant solution to this problem, but I cannot see the endgame. Does anyone have any tips for making this snippet more elegant? It's a very basic example, but one that I think is common programming challenge. If I have unknown number of lists of string variables of unknown length (It is unknown to me until runtime), how can I use just one loop or a loop plus a nested loop to create a matrice of the values?Easy to re-create. Create a VB.NET Form application, drag over two richtext boxes and a button, then paste this into the form class
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code].....
I want to write two nested loops and inside them "two if statements" when I write an Else statement which has a messagebox saying that ID is not found.. it repeated many times depending on the for loops. I only want to be displayed once !!! but when I wrote my code like this (using exit sub), the message appears when the condition is right and appears when the condition is wrong. I tried to move this statement somewhere else but still I have problems with it.
With EMPDataSet
For I = 0 To .Personal.Rows.Count - 1
For j = 0 To .Work.Rows.Count - 1
If EMP_CPR = .Personal.Rows(I).Item("CPR") Then
txtName.Text = .Personal.Rows(I).Item("Full_Name")
[Code] .....
I constantly find myself having to do code similar to the following.[code]Is there anyway to check for both on a single line? When i'm checking a condition for a great number of answers, I sometimes end up with conditionals 6-sets deep. If i check for null first, an error still pops up, even though VB shouldn't check since the first condition failed. i.e.[code]
View 8 RepliesI'm trying to implement parallel computing using .NET 4 on an asp.net website housed on a clustered server consisting of 6-8 dual core servers. My original script contains two nested For...Next loops iterating through a range of values in a grid of x by y.
For each point in the grid (x,y), we should perform a computationally intensive subroutine called MakePartsMatrix which accesses a SQL server database with dataviews and manipulating the local variable "unfilled" which is passed in ByRef.
Without the parallel implementation, the nested for loops work fine except its slow -- taking about 60 seconds to run.
When I parallelize the outer For loop, the script is about 50% faster, completing its calculations in 20-30 seconds which is great. However, I have noticed that the parallelization causes random parts of the grid to be either completely skipped (eg, grid (1,5) is never evaluated by the MakePartsMatrix), or some points in the grid (eg, x=10 & y=5) to be evaluated multiple times, resulting in duplicate work.
When I parallelized only the inner For Loop, the script execution time also improves by 50%, but now the last row (y-1) in the grid is skipped entirely and the results in "unfilled" are completely wrong.
When I comment out the "MakePartsMatrix" subroutine, the parallellization (either inner or outer For loops) does appear to visit every point of the grid (x,y) once, and only once.
Dim ConcurrentListofResults As ConcurrentQueue(Of FindBestResults)
ConcurrentListofResults = New ConcurrentQueue(Of FindBestResults)
Dim FBSResultsItem As FindBestResults
[Code].....
I have an arraylist of a "Doctor" class containing Firstname, Lastname,etc. Some elements in this arraylist may be duplicates of others. I am trying to iterate through the arraylist and search for duplicates. Once i find a duplicate i want BOTH duplicates put into another array and removed from the original array.
here is my function
Public Function createArrayOfDuplicatesAndRemove(ByVal st As ArrayList)
Dim duplicates As New ArrayList()
Dim i, j As Integer
[code]....
How could something be out of range if i start at the end and work to the front?
I am trying to code something with nested for loop with the following format:
[CODE]...........
However when the program hits the last value of 'For loop 1', the nested for loops seem to only trigger once instead of the number of times that i specified.
Private Sub populatedgv1()
'setup temptable to store Server data
Dim m_table As New DataTable
[CODE]........................
So I have some vb.net code, and I have a nested For loop inside a For loop, and then I have EXIT FOR statement, will it break out of one loop, or the whole chain?
View 2 Repliesthe purpose of the program is to display the monthly payments on the loan.My homework is to use do while loops instead of for loop.Here is the code for the for loop.
Option Explicit On
Option Strict On
Option Infer Off
[code].....
Now I'm having some trouble displaying the output using the do while loop, and I'm pretty sure it's a loop problem on my code. However, I cannot seemed to find out what's wrong. I looked at the examples of do while loop in my textbook, but I couldn't find anything useful to my problems of my program.This is the output for the do while loop.
Here's the do while loop code
Option Explicit On
Option Strict On
Option Infer Off
[code].....
When I use a For loop in a For loop the Contains Statement dosen't work! Even my custom one! I even tested mine and it works 100% And neither that or the String.Contains function work inside of For Loops And, I know both of them use loops to search through a string.
My function(It will atleast search once):
Function RealContains(ByVal load As String, ByVal needle As String) As Boolean
load = load.ToLower
[CODE].....................
How do you change an ADODB recordset to ADO.Net recordset?
View 4 Repliesso far i got
code
For Each item As Reflection.FieldInfo In GetType(NameSpace.ClassWithNestedClasses).GetFields
rtfAppend(item.Name & ":" & Tab & item.GetValue(Me))
Next
For Each item As Reflection.PropertyInfo In GetType(NameSpace.ClassWithNestedClasses).GetProperties()
[code]...
which gets me the simple string vars and properties of my top class, but how can i apply this to loop through all sub classes and get there vars and props?
I have a 5 by 5 matrix I want to populate and I would like to simplify this into for loops. As I understand, I would need 2 for loops to complete this task?
Dim x(4, 4) As Char
x(0, 0) = Mid(key, 1, 1)
x(0, 1) = Mid(key, 2, 1)
x(0, 2) = Mid(key, 3, 1)
[code]....
EDIT:I have a ItemList : Dim ItemList As New List(Of String)I wanna append each element from itemlist to a new list for 10 times each, then to start over again.How can I make a loop for each element while there are still elements in the list (10 times each)?I tried this but it's not working.
Private crt As Integer = 0
Private limit As Integer = 0
Private Function getline() As String
Dim line As String = ""
[code]....
but I didn't know where to add the 10 times limit and also the current item number(crt)
why this recordset is read only?
Sub PopMainForm()
Dim rst As ADODB.Recordset
Dim con As ADODB.Connection
[code].....
I get the following error when open the recordset: run-time error '-2147217904 (80040e10)' Method 'open' of object '_Recordset' fieldHow to solve the problem
Dim CONN As New ADODB.Connection
Dim RS As New ADODB.Recordset
CONN.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & App.Path &
[code].....
I used to work in VB.net and used Dataset's all the time when working with ADO, but now i'm Working in C# and the Research is showing me a lot of Recordsets.
Are they the same thing?
If no what is the difference?
how to negotiate a dataset via:
For Each dRow In quanDS.Tables(0).Rows
'do something to each row
Next
I now need to figure out now to loop through a subset of the records returned in the dataset - here's a VB6 example I need to convert:
strSQL = "select * from tblDQ order by xid, xcode, xDOS"
rsMaster.Open strSQL, conDB, adOpenDynamic, adLockOptimistic
rsMaster.MoveFirst
[code]....
I added a bindingsource and set the datamember to a table (in access) which has two fields. My bindingsource name is M and the field is usersT. how do i get its value?I tried:
dim tmp as string
tmp=M.item("usersT")
but this doesn't work.
I have an application in VB6 that joins 3 tables together to create 1 record set and I am able to use the move next and move previous methods to navigate through the record set.
I am having trouble creating this same scenario in vb.net with a data set. Do I have to create each table individually and then link them together somehow or can I join them all together in a query before I fill the data set?
I have a continious Form which opens and shows records of people with whatever criteria the user had chosen the screen before. When the form opens it checks which button was pressed and then changes the recordsource of the continious form.
When I try to edit the records it says "Recordset not updateable". I have done everything I can think of, I have change the type of recordset from dbopensnapshot to dbopendynaset.
VB6 code:
Private Sub Command1_Click()
Dim ccw As New ReceiveRecordsetFromVB6_VBNET.Class1
Dim rs As New ADODB.Recordset
rs.CursorType = adOpenStatic
rs.CursorLocation = adUseClient
[Code]...
How to sort a recordset using vb 6.0 coding?
View 2 RepliesIn this code i have a problem
Dim db As Database
Dim r As Recordset
Dim holder As string
Set db = OpenDatabase("c:database.mdb")
Set r = db.OpenRecordset("record1")
r.movefirst
[Code]...
To retrieve data from MS Access database I was using the following code to create a new Recordset. How can we declare it in VS 2008?
Public rs As New ADODB.Recordset
Set MSHFlexGrid1.DataSource = rs
Are the following codes above possible in VS2008?
Can i use SQLDataReader instead of a Recordset. I want to achieve the following result in an SQLDataReader.
Dim dbConn As New ADODB.Connection
Dim rs As New ADODB.Recordset
Dim sqlstr As String = "SELECT Name,Status FROM table1 WHERE id=" +
[Code].....
can i replace recordset with SQLDataReader and if I can can you please show me the changes in code.
how to create a recordset in ado.net?
View 10 Replies