I want to read the values from the database and convert it to a string array.
strQ = "SELECT * FROM Courses"
cmd = New SqlCommand(strQ, conn)
da = New SqlDataAdapter(cmd)
ds = New DataSet
da.Fill(ds, "Courses")
Dim i As Integer = 0
Dim j As Integer = 0
For i = 0 To ds.Tables(0).Columns.Count - 1
Me.ListView1.Columns.Add(ds.Tables(0).Columns(i).ColumnName.ToString())
Next
For i = 0 To ds.Tables(0).Rows.Count - 1
For j = 0 To ds.Tables(0).Columns.Count - 1
itemcol(j) = ds.Tables(0).Rows(i)(j).ToString()
Next
Dim lvi As New ListViewItem(itemcol)
Me.ListView1.Items.Add(lvi)
Next
I want to convert it to array format.
Edit from comments: Basically we're are dealing with courses and the number of students. The numbers are the student IDs who are taking the course. Here's some sample data:
jb(0) = {1,2,3,4,5} 'CIT121
jb(1) = {1,2,6,7,8} 'CIT141
jb(2) = {6,7,8,15,16} 'CIT202
jb(3) = {4,10,11} 'CIT203
You can use mentioned code
For i = 0 To ds.Tables(0).Columns.Count - 1
ds.Tables(0).Rows(i).ItemArray.[Select](Function(x) x.ToString()).ToArray()
Next
Related
I want to calculate the amount in a multiline Textbox where the value 0 is not found.
If TxtListScanValue.Text = ("2") Then
TxtDrawR2.Text &= Environment.NewLine & lastDraw2
Dim ListScan = TxtNumberListScan.Lines.ToList.Select(Function(o, i) New With {.scan = o, .Index = i})
Dim DrawR2 = TxtDrawR2.Lines.ToList.Select(Function(o, i) New With {.draw = o, .Index = i})
Dim list2 = From a In ListScan From b In DrawR2 Where a.Index = b.Index Select LstScan = a.scan, DrwR2 = ("00" & b.draw).Substring(("00" & b.draw).Length - 2) Order By DrwR2 Descending
TxtListScanTxt.Text = String.Join(vbCrLf, list2)
End If
If TxtdrawR5 =
2
4
0
0
1
3
5
In output I want to display: 5 because:
I want to calculate the count lines where the value 0 is not found. Count lines no have 0 value :D (2+4+1+3+5 = 5) (5 lines no have 0 value).
You create function like this:
'For Counting
Private Function CountNonZero(ByVal TheCtrl As TextBox) As Integer
Dim myCnt As Integer = 0
For Each Content In TheCtrl.Lines
Dim ContentVal As Integer = 0
Integer.TryParse(Content, ContentVal)
If ContentVal <> 0 Then myCnt += 1
Next
Return myCnt
End Function
'For Counting
Private Function SummingNonZero(ByVal TheCtrl As TextBox) As Integer
Dim mySum As Integer = 0
For Each Content In TheCtrl.Lines
Dim ContentVal As Integer = 0
Integer.TryParse(Content, ContentVal)
If ContentVal <> 0 Then mySum += ContentVal
Next
Return mySum
End Function
And you can count or sum now:
dim TxtdrawR5Count as integer = CountNonZero(TxtdrawR5)
dim TxtdrawR5Sum as integer = SummingNonZero(TxtdrawR5)
This is the beginnings of a timetabling algorithm. The problem is with inserting a member into a group, but I have included the whole subroutine here for context. The table "membergroup" has 2 headings, MemberID and GroupID. No error code is thrown, but the table does not receive the new record.
I have gone through it line by line, and the values for iMember_Choice.MemberID and groupID_to_insert are correct.
Dim numberofrooms As Byte = rm.Count
Dim possiblerooms(numberofrooms + 1), possibleroomcounter As Int32
For TimeTableNumber = 1 To Val(NumberOfTimetablesToCreate.Text)
Dim memchoic = (dc.ExecuteQuery(Of memberChoice)("SELECT * FROM MemberChoices ORDER BY NEWID()")).ToList 'Orders list randomly
'sort into array for each rank, so highest ranks are allocated first
Dim Member_choices_Table_ordered_by_rank = From q In memchoic Order By q.Rank
For Each Member_Choice In Member_choices_Table_ordered_by_rank
ProgressBar.Value = ProgressBar.Value + 1
Dim iMember_Choice As memberChoice = Member_Choice
'Dim memactpossibleinstance(maxmemchoicernk, n) As memactvpossibleinstance
For Each room In rm
Dim rmid As Int32 = room.RoomID ' finds rooms activities can be in
If Not (From rom In roomact Where rom.ActivityID = iMember_Choice.ActivityID And rom.RoomID = rmid).FirstOrDefault Is Nothing Then 'finds suitable rooms
possiblerooms(possibleroomcounter) = rmid
possibleroomcounter = possibleroomcounter + 1
End If
Next
'find possible times
Dim roomid_to_insert, current_maximum_rank As Integer
Dim period_to_insert As String = "MonAM"
Dim staffact_that_can_do_this_activity = _
(From q In staffact Where q.ActivityID = iMember_Choice.ActivityID)
For roomcount = 0 To possibleroomcounter - 1 'for each room in roomcount, find rank for room
Dim rmid As Int32 = possiblerooms(roomcount)
For Each time In periods
Dim itime As String = time.Period
Dim Rank As Int16 = member_Error_check_period_count(iMember_Choice.MemberID, itime)
If Not (From rav In rmav Where rav.RoomID = rmid And rav.Period = itime) Is Nothing Then 'room is free
Rank = Rank + 12
Else ' room has an activity
Dim GroupID_now = (From q In instnce Where q.Period = itime And q.RoomID = rmid Select q.GroupID).SingleOrDefault
If GroupID_now <> 0 Then
Dim groupActID_now = (From q In grp Where q.GroupID = GroupID_now Select q.ActivityID).SingleOrDefault
'Dim activity_now = (From q In actv Where q.ActivityID = groupActID_now).SingleOrDefault
If groupActID_now = iMember_Choice.ActivityID Then 'Good, this activity is already on in this room
Rank = Rank + 50
If (From q In memgrp Where q.GroupID = GroupID_now).Count > 4 Then
Rank = Rank - 50
End If
End If
End If
End If
If Rank > current_maximum_rank Then
current_maximum_rank = Rank
roomid_to_insert = rmid
period_to_insert = itime
End If
Rank = 0
Next
possibleroomcounter = 0
Next 'for each room possible
Dim groupID_to_insert As Integer
If (From q In instnce Where q.Period = period_to_insert And q.RoomID = roomid_to_insert).FirstOrDefault Is Nothing Then
groupID_to_insert = insert_ins_group(period_to_insert, roomid_to_insert, iMember_Choice.ActivityID)
Else
groupID_to_insert = (From q In instnce Where q.Period = period_to_insert And q.RoomID = roomid_to_insert Select q.GroupID).SingleOrDefault
End If
'PROBLEM PROBPBLY HERE/////////////////////////////////////
memgrp.InsertOnSubmit(New membergroup With {.MemberID = iMember_Choice.MemberID, .GroupID = groupID_to_insert}) 'PROBLEM PROBABLY HERE
dc.SubmitChanges()
current_maximum_rank = 0
Next 'for each memberchoice
dc.SubmitChanges()
Next 'timetabl no
dc.SubmitChanges()
memgrp is initiated as
Dim memgrp As Table(Of membergroup) = dc.GetTable(Of membergroup)()
I want to add characters (like % and pp) in values stored in a DataTable, but I'm getting an error message:
Input string was not in a correct format.Couldn't store <97.0%> in Actual Column. Expected type is Decimal.
How can I change the type of values that the DataTable can store?
Dim dv As New System.Data.DataView
Dim dt As New System.Data.DataTable
dv = SQL_Customer.Select(DataSourceSelectArguments.Empty)
dt = dv.ToTable()
dt.Rows(1)(1) = CStr(dt.Rows(1)(1)) & "%"
dt.Rows(1)(2) = CStr(dt.Rows(1)(2)) & "%"
dt.Rows(1)(3) = CStr(dt.Rows(1)(3)) & "%"
dt.Rows(1)(4) = CStr(dt.Rows(1)(4)) & "pp"
You can't change the type of a data table column once it's filled.
One work around is to add a new column of type string and then populate that column with the string values you need and then delete the column that is of the type you don't need.
If this helps someone, this is how I resolved the problem:
Dim dv As New System.Data.DataView
Dim dt As New System.Data.DataTable
Dim dt2 As New System.Data.DataTable
Dim SelectedIndex As Object
If datagrid.SelectedIndex = "-1" Then SelectedIndex = 0 Else SelectedIndex = GV_Cust.SelectedIndex
'Populate Dataview with data in SQL Query for Customer KPIs
dv = SQL_Customer.Select(DataSourceSelectArguments.Empty)
'Populate table with data from dataview. Note that the data is formated as per data loaded. So if number is loaded, then format for the cell is number. This creates a problem when adding percentages
dt = dv.ToTable()
'New colums are added as string format in the dataTable so that % and pp can be added
Dim column As DataColumn
For i = 1 To 6
' Create second column.
column = New DataColumn()
column.DataType = System.Type.GetType("System.String")
column.ColumnName = i
column.AutoIncrement = False
column.Caption = i
column.ReadOnly = False
column.Unique = False
' Add the Column to the DataColumnCollection.
dt.Columns.Add(column)
Next
'New columns are populated and calculations for variances are calculated
For j = 0 To 2
For i = 0 To 4
dt.Rows(i)(7 + j) = dt.Rows(i)(1 + j) & "%"
dt.Rows(i)(10) = (dt.Rows(i)(1) - dt.Rows(i)(2)) & "pp"
dt.Rows(i)(11) = (dt.Rows(i)(1) - dt.Rows(i)(3)) & "pp"
dt.Rows(i)(12) = (dt.Rows(i)(2) - dt.Rows(i)(3)) & "pp"
Next
For i = 5 To 6
dt.Rows(i)(7 + j) = dt.Rows(i)(1 + j)
If dt.Rows(i)(2) = 0 Then dt.Rows(i)(10) = 0 & "%" Else dt.Rows(i)(10) = Math.Round((((dt.Rows(i)(1) / dt.Rows(i)(2))) - 1) * 100, 1) & "%"
If dt.Rows(i)(3) = 0 Then dt.Rows(i)(11) = 0 & "%" Else dt.Rows(i)(11) = Math.Round((((dt.Rows(i)(1) / dt.Rows(i)(3))) - 1) * 100, 1) & "%"
If dt.Rows(i)(3) = 0 Then dt.Rows(i)(12) = 0 & "%" Else dt.Rows(i)(12) = Math.Round((((dt.Rows(i)(2) / dt.Rows(i)(2))) - 1) * 100, 1) & "%"
Next
Next
'Old columns are deleted and new wones are renamed
dt.Columns.Remove("A")
dt.Columns("1").ColumnName = "A"
dt.Columns.Remove("B")
dt.Columns("2").ColumnName = "B
dt.Columns.Remove("C")
dt.Columns("3").ColumnName = "C"
dt.Columns.Remove("D")
dt.Columns("4").ColumnName = "D"
dt.Columns.Remove("D")
dt.Columns("5").ColumnName = "E"
dt.Columns.Remove("F")
dt.Columns("6").ColumnName = "F"
'Customer grid is populated, a selection button is added and the first row is selected
datagrid.DataSource = dt
datagrid.AutoGenerateSelectButton = True
datagrid.DataBind()
datagrid.SelectedIndex = SelectedIndex
I need to count from 0 - 9999 in VB. How can I make the format 0000 - 9999, so that the output is:
0000, 0001, 0002, 0003, .......
I used the following code
Dim p4num As Integer = 0
Dim p3num As Integer = 0
Dim p2num As Integer = 0
Dim p1num As Integer = 0
p4num += 1
If p4num = 10 Then
p4num = 0
p3num += 1
If p3num = 10 Then
p3num = 0
p2num += 1
If p2num = 10 Then
p2num = 0
p1num += 1
End If
End If
End If
but I would do it in another way. Any idea?
The ToString() may help. How about
myint.ToString("0000")
or
myint.ToString("D4");
For i as integer = 0 to 9999
Debug.WriteLine(i.ToString("0000"))
next
Untested code, but should work...
Your guide
Dim numbers As IEnumerable(Of Integer) = Enumerable.Range(0, 9999).ToArray()
'object j = string.Join(", ", numbers);
For Each item As var In numbers
Console.WriteLine(item.ToString("#0000"))
Next
Bellow pls find the code in VB 2008. I must sum up the numbers in the xlistscorebox
Dim tot As Integer
Dim scoresentered As Integer
For index As Integer = 0 To Me.xListscoreBox.SelectedItems.Count - 1
tot = tot + Val(Me.xListscoreBox.SelectedItems.Count)
For se As Integer = 0 To Me.xListscoreBox.SelectedItems.Count - 1
scoresentered = Me.xListscoreBox.SelectedItems.Count
Next
Next
Me.xscoreave.Text = tot / scoresentered.ToString
Me.xtotalscoreTextBox.Text = tot.ToString
Me.xtotscoreentered.Text = scoresentered.ToString
The issue is that the calculation is giving wrong results.
Any comment will be highly appreciate.
Cecilia
Dim TotalScore as Integer
For Each x As String In Me.xListscoreBox.SelectedItems
TotalScore = TotalScore + Convert.ToInt32(x)
Next
dim AverageScore as Decimal = TotalScore / Me.xListscoreBox.SelectedItems.Count
dim ScoresEntered = Me.xListscoreBox.SelectedItems.Count