I am having some trouble with creating a simple function that converts a column of a datatable to an array (containing all numbers). Upon running it, it says "Index was outside the bounds of the array"; however, I couldn't understand why my function would create this problem.Also since I do not usually program using VB.Net, I am not sure if my function has other errors (like syntax errors).
View 2 RepliesI have a datatable which has 5 column. It is possible to copy only its 2 column in and save it into new datatable.I used this code but it copies all the 5 column
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj).CopyToDataTable
i used this one but it is not supported
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj.item("Column1"), obj.item("Column2")).CopyToDataTable
I am getting array of selected datarows from a datatable.select.I use the commands below to get that array or datarows
Dim foundRows() As DataRow
strExpression =
Here is what I tried.I have looked at examples by MS but they all just write to the screen and I have no interest in that.
For Each rowWork In foundRows
dtWork.Rows.Add(rowWork)
Next[code]....
"LineOfBusiness = 'CPP'"
foundRows = modXchange.pdtWork.Select(strExpression)
Now, I want to place the rows from foundrows into an empty data table.I did what I thought was the obvious but that only returns a bunch of rows with no data
I need help converting DataTable to XML. I have done it using LINQ but I can't get exactly as I have to. I made a picture so that you can easily understand. The XML needs to be in certain format like below so I can't just use dt.writexml(). Artist ID needs to auto number. Songs are groupped by Artist. Prefer a solution in Linq coz that's what I have used throughout the project but I coundn't manage to get what I want here. The columns names are known so you can use something like this in the code. row.Field(Of String)("title")[code] i also have some more code that will query first created xml and do the grouping but still having album="albumname" in the song element as attribute. And it should be just one query from datatable to xml.i hate having to query against xml again to just refomat it.[code]
View 2 RepliesI'm trying to use the JavaScriptSerializer to work with this code. However it crashes when it reaches the last line;
Dim json As New String(sr.Serialize(dt))
I get this error message;
A circular reference was detected while serializing an object of type 'System.Reflection.Module'.
I need help converting datatable to xml using Linq. I could do it with hardcoded column names as you can see in my code .. but i need it without hardcoding it ..Example datatable ..My linq query ..
Dim xmlDoc As New XDocument(
From row In dt.AsEnumerable()
From row In dt.AsEnumerable()[code]......
I am trying tomodify the following code from a datagrid to a datagridview but I'm not sure about how to do the conversion. The problem lies with theDataGrid.TableStyles.A dgv does not have that property.
Function
GetColumnHeadingText(ByVal
Column As
[code].....
I have a "result" which is DataTable and I like to get the x distinct values(City) and convert it back to DataTable how do I do this the code below gives me an error
Dim query = (From x In results.AsEnumerable()
Select (x.Field(Of String)("City"))).Distinct().CopyToDataTable()
so what I want is records of distinct cities I can get that but the problem I am having is converting it back to Datable.
Edited:I am using "where" in this statement and it does convert to Table(works fine) but not on "select"
Dim results = (From myRow In ds.Tables(1).AsEnumerable()
Where (myRow.Field(Of String)("xxxx") = xxxx)
Select myRow).Distinct().CopyToDataTable()
I have a data table, i want to add a new column on that table, the data in that new column will depend in the data from another column. Now i can think of two ways to accomplish this, first is loop through the whole table and do the statements to get my new columns appropriate data. the second approach would be to give the new column an expression, then convert the table to xml (to remove the expression) then convert the xml string back to datatable.
Now, is there any other way around this? what could be the most optimized way in solving this task?
just hoping that someone may be able to assist me to convert system.array to double() array.
Declarations are as follows:
Private f_Data As System.Array
Private f_Measures() As Double
Private f_NumberOfObservations As Integer
I then 'fill' f_Data from a range in an Excel worksheet as follows:
f_Data = wsXLSData.Range(wsXLSData.Cells(1,1), wsXLSData.Cells(8, 1)).Value
This seems to work OK. Upon checking f_Data is indeed filled with 8 double type numbers.
I then try to convert this system.array to a double array as follows:
For i As Integer = 0 To f_NumberOfObservations - 1
f_Measures(i) = f_Data(i + 1, 1).value
Next
I then get an error pointing to the line ' f_Measures(i) = f_Data(i + 1, 1).value' of type MissingMemberException was unhandled by user code'
I am currently writing unit tests for an application near completion (before management looks at it and turns it inside out). I am testing the business layer and a method is set to return a datatable of all "GroupID"s, which are simply an integer to represent the group that a user belongs to.
I'm assuming the best way to assert on this unit test would be to assert that the correct groupIDs are being returned from a controlled test database. However, I'm not sure how to assert on a datatable. Is the only (and best) possible way to accomplish this to simply loop through the datatable until it's empty and add each value to an array of integers? How would one go about asserting on this test?
After Filling a DataTable in GridView's DataSource . A column with check box Type appears but it created as read only column and I can't enable it or make it editable... even i tried .readonly = false and still can't be edited
View 1 RepliesOkay I am working on a Voice Recognition Application that has a chat bot in it. When voice is recognized it converts the recognized string into an array and checks if the first or last value of the array is either computer or the Bot's Name. However, I am still very new to VB.NET only been programming in it for a few days. (I know ASP and VBscript really well though) When it goes through the check I get an exception how do I fix this? Here's my code with a comment on the line that it fails on:
Private Sub OnReco(ByVal StreamNumber As Integer, ByVal StreamPosition As Object, ByVal RecognitionType As SpeechRecognitionType, ByVal Result As ISpeechRecoResult) Handles RecoContext.Recognition
Dim recoResult As String = Result.PhraseInfo.GetText 'Create a new string, and assign the recognized text to it.
[code]...
I have a string say, str = "system.Int16" I want to add a column in DataTable say, dt = new DataTable()I want DataType for that column as per 'str', i.e. System.Int16 Then How to? dt.Columns.Add("MyColumn", ...)
View 2 RepliesI have a 2d array of data that I have performed the sum of the individual column of the 2d array. I want to send the results to a datagridview and also will like to have the result as a 1d or 2d array.
Below is sample of my code
Dim Array1(,) as double
Array1(0, 0) = 5
Array1(0, 1) = 7
[code].....
Can't add a new column for DataTable
View 2 RepliesI have a dataset with just 1 datatable and 1 row but with 2 columns.I want to get the value of the 1st column.How can I get it in vb.net
View 3 Repliesi have a Datatable having following result from database
ID Name Class FeeName Amount
9 gumman hgjgh 6Th Fine 0
9 gumman hgjgh 6Th Tution Fee 3000
9 gumman hgjgh 6Th Lebority Fee 500
10 AAdil Hussain 5Th Fine 0
[Code]...
I have a sql stored procedure that returns a certain group of columns in my datatable. How can I move (let's say) the column in the first position, to the last position before I export the datatable to excel ?
Dim myConn As New SqlConnection(strConnection)
Dim myCmd As New SqlCommand(strSQL, myConn)
Dim dt As DataTable = New DataTable()
Dim da As SqlDataAdapter = New SqlDataAdapter(strSQL, myConn)
[code]....
I have a csv file that comes in I put it into a dataset and do a little manuipulation of the appearance of how the data is presented and then I put it back out into a different csv file that our 3rd party application will except. I was importing it into SQL Server and then doing a select statement to grab the data back out in the format I required. However I'd really like to eliminate the need for the SQL Server use.
So my question is how do I add in the 1st column of a CSV file the column name "KC" with a value of "1" there will only be 1 rows worth of data, mind you it's 55 columns long but there is nothing I can do about that, it's the way it has to be.So do I do this in the DataTable or when I create the CSV file? And how do I do this?
[Code]...
Is it possible to have a button column in a data table like there is in DataGridView?
View 2 RepliesI need to limit the amount of columns being returned from a datatable from 14 to 5 or 6. Date, Hour and 3 to 4 decimal columns. Is it possible to do something like a SQL 'Like' to specify which columns I want?
View 8 RepliesSo i create a datatable from a table i can't directly view(i.e. using sql server management). I want to find the column names that are in the datatable, what would be the correct way do this?
View 3 RepliesHow to insert a column in datatable at Perticular index in vb 2003.
View 4 RepliesI need to Quarry from Data Table Like
select Name, Address from myDataTable where name = 'x'
and
select distinct(name) from myDataTable
What's wrong with my LINQ query ?
Dim s = (From rowItem In i.AsEnumerable() _
Select rowItem("COUNTER")).Sum()
I'm trying to Sum all the value in column 'Counter' in my Datatable. 'Overload resolution failed because no accessible 'SUM' accepts this number of arguments.
My problem is that i want to use the Compute method for a datatable.[code]The name of the column of that i want to sumarize is 2012, but it seems that the compute method doesn't recognize it as a column and throw this exception Syntax error in aggregate argument: Expecting a single column with a qualifier 'Child'.It is not possible to me to change the name of the column, what can i do in this case to sumarize the datatable and save it in a variable
View 4 RepliesI have following codes
str2 = "select sno,name from employees where sno =" & Val(Me.TextBox1.Text)
cmd2 = New SqlClient.SqlCommand(str2, con)
da2 = New SqlClient.SqlDataAdapter(cmd2)
dt2 = New DataTable
da2.Fill(dt2)
Now dt2 has two columns as sno and name
But I want to add a 3rd column city type char(80)
I have an unbound Gridview that is populated by a Linq to Entities query and would like to convert string values in a particular column to lowercase. In the Gridview's RowDataBound event, I have tried StrConv(e.Row.Cells(3).Text, VbStrConv.ProperCase) but this doesn't work. I have also tried StrConv(emp.Name, VbStrConv.ProperCase) in the LiNQ to Entities query but still the Name values returned are to converted to Lower-case.
Protected Sub GridView3_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView3.RowDataBound
If e.Row.RowType = DataControlRowType.DataRow Then
For i As Integer = 0 To e.Row.Cells.Count - 1
Dim cellDate As Date
[Code] .....
I am looking for any assistance on the best method to accomplish this task. I need to take a comma delimited text file, load it into memory, and then grab indevidual columns of data and export them to a file.[code]I need to for this project I ma working on grab ALL of COL C for example and export it and the data to that column to a file. Can someone provide me with assistance on the best and easiest method on doing this? I know I can do it with a lot of parse text's and many methods of using a listbox or arrays but I'd like to explore some options.
View 6 Replies