Preventing Empty Columns From Loading In A Datacolumn?
May 11, 2011how to prevent an empty column in Excel to be loaded into a dataset column?
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Prevent Empty Columns From Loading In A Datacolumn?
Aug 13, 2009Prevent an empty column in Excel to be loaded into a dataset column?
View 3 RepliesLoading Line Into ListBox - No Empty Items
Dec 15, 2011I've got a Program and a text file, this text file gets load into the list box but that's not the problem. The problem is that when I make the text file it makes a open line and this line gets loaded into the list box and I don't want empty items.
So here's code that I use to make text file
Public MySettingfile As String = My.Application.Info.DirectoryPath & "Process History.MemFreo" Dim myCoolWriter As New IO.StreamWriter(MySettingfile, True, System.Text.Encoding.Default)
myCoolWriter.WriteLine()
myCoolWriter.Close()
VS 2008 Remove Empty Columns From A Tab Delimited Text File?
Dec 13, 2009How can I open a tab delimited text file and remove the columns that are empty and the save it? Empty columns are those that have no value in the first row.
View 7 RepliesAssign A Populated Datatable's Columns To Another Empty Datatable?
May 28, 2007Is there a simple way to assign a populated datatable's columns to another empty datatable? That is, I want to copy a datatable's structure only but not its data.
View 6 RepliesWay To Create Empty Data Table / Update Its Contents Based On Columns Not Add Data Based On Addition Of New Rows
Apr 6, 2011I am creating a project in VB.NET in which one of the reports require that the name of employees should be displayed as column names and whatever work they have done for a stated period should appear in rows below that particular column.Now as it is clear, the columns will have to be added at runtime. Am using an ODBC Data source to populate the grid. Also since a loop will have to be done to find out the work done by employees individually, so the number of rows under one column might be less or more than the rows in the next column.Is there a way to create an empty data table and then update its contents based on columns and not add data based on addition of new rows.
View 1 RepliesPossible To Have A DataColumn With Space In Name?
Feb 17, 2011I have a DataTable that I am creating and binding to a GridView. Currently the headers do not have any spaces and it makes it hard to read. I want to space them out but I'm having a minor issue.[code]I know that I can set the HeaderText in the columns declaration like below, but I won't know how any columns I am going to have. And would rather the columns be generated automatically. [code]
View 2 RepliesAsp.net - Adding A DataColumn To A DataTable?
Nov 22, 2010How do I go about adding a ButtonColumn to a DataTable.
I am basically using a DataTable as the DataSource of a DataGrid and need to add a ButtonColumn to the DataTable so that when I DataBind it to the DataGrid it all works.
Although when I try
dt.Columns.Add(buttonColumn)
This is not allowed. It has to be a basic DataColumn.
VS 2005 Can Not Bind To DataColumn
Feb 5, 2011Anyone have any ideas what would prevent my data from not be ing able to be bound to my data column? [code]My error says cant bind to column named SellingPrice? I have many other columns ALL binding the same way and other parts of my program recognize SellingPrice ?
View 9 RepliesChange When An Expression In A Datacolumn Is Evaluated?
May 28, 2012Is there a way to change when an expression in a datacolumn is evaluated?
I'm trying to make a simple total function which sums the values of a particular column in a data grid. Normally the expression is evaluated when I leave from the datagridview, but I wish it to be evaluated when the row is changed.
Default Value Of String.Byte[] Datacolumn
Aug 13, 2010in my datatable I've a String.Byte[] column which contains the array of bytes of an image. So, when the datatable is binded to the datagrid, I can see the picture, if present, and the red cross if is not presente. So I can remove the red cross, by assign a value to the DefaultValue property of the datacolumn. But what default value I've to assign?? I tried with system.dbnull.value but the red cross is still present.
View 8 RepliesVS 2008 Comparing An Array With The DataColumn?
Dec 28, 2009First of all - It`s my first post here so welcome I have a short question.I have an array with strings values, and a datacolumn with values of the same data type. The question is - what is the most efficient method to find values which are in the array, but aren`t in the datacolumn?
View 18 Replies.net - Get An Specific Row Or Cell Value From A DataColumn Object With No Using A DataGrid?
Aug 20, 2009This is the code I have:
Sub Main()
Dim dts As New DataSet
Dim da As New SqlDataAdapter
Dim SolTabla As New DataTable
[code]....
For example, I want to access the second cell value in "Columna". How can I do this with no using a Datagrid?
.net - Update DataColumn's With Latest Column Information?
Nov 26, 2009I have a dataset with a number of data columns, due to sizing issues I've updated a number of the varchar columns from say VARCHAR(20) to VARCHAR(50).I'd like the DataTable to automatically grab the new column information, is this possible? I'd rather not go through each column in the table and update the length.
View 1 RepliesCustom Function For Datacolumn.expression Property
Jan 23, 2009i read an article about datacolumn.expression property here [URL]. this is really great. but i was just wondering, for my case i want to use my custom function to use in the expression. basically, on my datatable i added an unbound column AGE. when i display records, i just want the age textbox to be populated with the computation of the person's age based on birthdate.
View 7 RepliesRemove Time Part In DateTime DataColumn?
Jan 17, 2011I defined a DateTime datacolumn in a datatable dt as [code]]....
View 5 RepliesVS 2005 - Adding DateTime DataColumn To DataTable?
Jun 16, 2010I'm adding a DateTime DataColumn to a DataTable like this:
Dim colDate As DataColumn = New DataColumn("Date")
colDate.DataType = System.Type.GetType("System.DateTime")
dt.Columns.Add(colDate)
Then when I try to add it to my datatable, if the value is Nothing I get an error saying string was not recognized as a valid DateTime. I'm having trouble getting this to work.
VS 2005 Shifting The Position Of A Datacolumn In A Datatable?
May 21, 2009Can anyone demonstrate with an example how to shift the position of a datacolumn in a specific position after it is added at the end of a datatable.For example lets say I have a datatable with 9 columns and 5 rows. Now I added a 10th column. However I need this new column as the 5th column which requires shifting. How do I perform this shifting?
View 3 RepliesVS 2010 Unique DataColumn With Several NULL-values?
Jan 17, 2011I'm using MySQL to store some numbers. One of the columns in the database is defined as unique, but it does allow multiple NULL-values. That is exactly how I want it.ut when I'm trying to load the data into my strongly typed DataSet, I get a error saying that a constraint fails... I do understand why that happens (several rows with NULL-values in a unique column), but is it a way to keep a DataColumn in vb.net unique, but still allow several rows with NULL-values like in MySQL?
View 2 RepliesDatacolumn Expression Subtracting Dates And Taking To Datagridview?
Dec 3, 2009datacolumn expression subtracting dates and taking to datagridview
View 1 RepliesFormat DataColumn Values In DataView.Filter Expression?
Jun 11, 2012I am trying to build a filter string for my DataView, but I have run into a problem. My underlying DataTable contains values that are formatted when displayed in my DataGridView.For example, if the DataColumn contains 1.52 and the DataGridViewColumn.DefaultCellStyle.Format = "n0" then 2 is displayed.So the user sees 2, then sets the DataView.RowFilter = "DataColumn = 2", and no DataRows are returned. Is there a way to format the DataColumn in the RowFilter string? For example, DataView.RowFilter = "FORMAT(DataColumn, "n0") IN (2, 4)". This filter string should return 3 rows. If not, can LINQ do this?
View 5 RepliesShow Rich Text In A Cell Of A Datacolumn Of A Datatable?
Jan 14, 2010I am currently working with a datatable and I want to be able to show richtext in a column of the table. First question can this be done? I can force the column to be Type Of richtext box. However, when I try to view/display the table, I get something like..."System.Windows.Forms.RichTextbox, Text: Text That I have added" in the column.
Is there a way that I can get it to show the rich text in a cell of a datacolumn of a datatable?
Storing String Item In A Date / Time DataColumn Of A DataTable
May 27, 2009I have a datatable which loads data from an Excel Spreadsheet. One of the columns in the Excel SpreadSheet was of type "Date/Time" in which date values are stored. Now I appended the datatable with three new rows and I wanted to store string values in these rows using the code below. However due to the fact that one of the columns are date/time type, an error is generated as date/time column does not accept string value. I have two questions
a. Is it possible to store string value in date/time DataColumn?
b. Is there a remedy to this situation? [code]
VS 2008 DataColumn And Call MaxLength Property On It To Get Length Of Data
Sep 16, 2009I have a DataColumn and call the MaxLength Property on it to get the length of data that can go into a field ... but it always returns -1 (yes even on a string field).
View 8 RepliesVS 2010 : DataColumn.Expression Which Calculates Difference Between Two DateTime Values?
Jan 13, 2011I have a DataTable with two DateTime columns: "start_time" and "end_time".Now, I want to add a third column that calculates the difference between the two DateTimes. But I can't seem to figure out how. I've tried to set the .Expression-value to "start_time - end_time", but it says that "-"-operator is not allowed on DateTime.
View 4 RepliesDataGridView, Set Up Columns, Populate Data Table, Bind, But Not Using Columns Created In Code?
Oct 26, 2011I'm using VB.net 2005. I have working programs that I populate DataGridViews with something like the following:
[Code]...
Preventing SQL Injection?
Oct 25, 2010I have this code
UPDATE OPENQUERY (db,'SELECT * FROM table WHERE ref = ''"+ Ref +"'' AND bookno = ''"+ Session("number") +"'' ')
How would I prevent SQL Injections on this?
[code].....
Multiple UI Thread - Show An Animated Loading Gif Image Till Data Loading Is Completed In All Text Boxes
Jul 13, 2009I have a window application develpoed in vs 2008, framework 3.5, in which i have put a button.. Now where i click that button the other text boxes are filled up with the data from database thru web service.. what i want is while all text boxes are being filled i want to show an animated loading gif image till data loading is completed in all the text boxes.. i have tried to use image picture box but while data is loading gif image is displyes but in static mode.. cant see animation... i think this is because data loading and animation both are done thru one UI thread..
View 8 RepliesAdd/subtract/divide/multiply Certain Columns And Place The Information Into Other Columns?
Nov 30, 2010My goal is to connect to my database either manually or using an sqladapater, and get information from two of my databases on sql server 2005. Then I want to take this information and on run-time begin to add/subtract/divide/multiply certain columns and place the information into other columns. I can do this in queries, however, I want to do it on run-time what is the best way to achieve this.I had some of this working, but I just want to start fresh and see how you would go about doing this.
[Code]...
DataGridView - Convert Nulls To Empty Strings And Display It In The Grid As Empty Strings
May 14, 2009I have a DataGridView that has some columns with dates. It binds to an in-memory Datatable which gets loaded from an string array of data passed back from the backend Some of the rows returned have nulls for the date columns. Solution 1: If I define the Date column in the DataTable as "string" I can easily convert those nulls to empty strings and display it in the grid as empty strings (desired results). However, if the user clicks on the date column header to sort by date, it doesn't order the rows as you want. You get a purely string sort order. Not acceptable
[Code]...