Reading A Blank String From Excel When Trying To Read The Header Of A Data Column?
Aug 25, 2011
I use an OLEDB connection to read from an excel database, and this loop to read in all of the data from each of the columns
While reader.Read()
For i As Integer = 0 To reader.FieldCount - 1
temp = reader(i).ToString + ControlChars.Tab
output_file.Write(temp)
[code]....
Some of the columns contain date information, which are read in fine (usually as a string "2/20/2011" or so), but the headers of those columns are read in as a blank "". The headers for all the other columns read in fine, but not for the date containing columns.
I have never read from an excel file in VB.NET before so sorry if anything is off.I am downloading an .csv file from a vendors ftp service that has 8 columns ( style # - mfr.item # - description - metal type - availability - center weight - total weight - retail value )I am trying to retrieve all data in the rows bellow style # and retail valuethere are roughly 4,649 rowsI am not sure how to do this.
I load the excel file using the microsoft.office.interop.excel: Dim eApp As excel.Application Dim eBook As excel.Workbook
Im new to this .NET programmin...i just need to know some basic stuff abt readin data from excel..I just use ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + p_fileUrl + ";Extended Properties='Excel 8.0;Mode=Read;IMEX=1;'") to read data.in a particular column,first ten or below cells hav no values and the rest has values.
The problem is that for some columns it sets the data type to be Double even though the spreadsheet column format is "Text" and teh column contains non-numeric data. Then when it gets to that cell it returns DBNull instead of the text value.
My Visual Basic .Net 2010 application reads data from an EXCEL spreadsheet which will be generated by my "customers". The responses to Alkis last year (23 July 2011) has been a big help and got me over a hump in my application. Now I am down to the last issue - how do I detect a blank cell? Valid data is numeric, starts at a fixed cell (A5 to be specific), and will be continuous until it ends with blank cells. While blank cells appear to print a "zero", when I try to use zero as an end criteria I get a 'System.InvalidCastException'. When I put in a specific end value (-1) in the last cell all works fine but that, of course, is an invitation to a user error.What is the difference between "Value" and "Value2" and where might I find documentation that explains the difference? [code]
Looking at deleting columns in excel and have found several threads that show how to delete an entire column which I have tested and done successfully. These columns were all identified by "A", "B", "C" and so on...
I was wondering if it was possible to do the same thing using the column headers. When deleting the columns in excel, one has to keep in mind that columns deleted from the left will shift the entire sheet to the left and if one is not careful, the next column[code]...
Let's say a user wants to delete the 'Middle' column (assume as column B in excel) and then delete the 'Suffix' column (assums as column D in excel). If they don't know to work from right to left when deleting columns, they would write code that would delete Column B and then repeat that code for Column D. However, once column B is deleted, all columns will shift left, which will result in the 'Phone' column (formerly column E now column D) being deleted instead of the 'Suffix' column (formerly column D now column C).
If there was a way to delete the columns by their headers (i.e. Middle, Suffix...) this would eliminate the problem; to me it seems a bit more intuitive as well.
how do I get the Header text of the header the user clicked in the datagridview.I know I have to use the column header click event but I can't work out or find away to extract the clicked header data?
I am Importing a Excelsheet(xls) in to my Application, but the date and Number column showing blank in dataset when comes to application. The values are there in Excel. Any other way to import the excel sheet to application, so that i should get all the values same as there in the excel sheet.
I have a weird requirement to parse a file which is a comma separated string with repeating header..i have a file which i load into database and this gets populated as a single column string with header and details data:something like this (This is single COLUMN String in a table). SSIS is not able to handle this so i am trying to know..If it is possible using writhing VB.Net custom component.[code]Also, if i can pass the values of header (i.e. header3, header5, header7 and header10) as a variable would be ideal.
i want to binding excel data to a datagrid without no header, just the data.for example :my excel files consist of 3x3 matriks data in 3x3 excel cell like this
1 2 3 4 5 6 7 8 9
and i want to show all this data on data grid i have tried with some code like this
Dim MyCommand As System.Data.OleDb.OleDbDataAdapter Dim ds As New DataSet MyConnection = New System.Data.OleDb.OleDbConnection("provider=Microsoft.Jet.OLEDB.4.0; " & _
[code]....
but the first row of that data ( 1 2 3 ) is not shown up in the datagrid, just the 2nd and the 3rd row that shown up in datagrid?
I'm currently writing a small app that takes data provided by an SQL stored procedure and makes it available for easy export for non-tech savvy users. I'm trying to make this as generic as possible, in that you should be able to plug in just about any SP and follow my template to have an export utility. I'd like to add a way to get the column names before running the SP from the SP itself. I had assumed you could just run the SP with impossible values so nothing is returned, then get the columns from the resulting VB.NET DataTable. However, if there is no data returned, the column names aren't returned either. How can I get the column names from the SP without having to hard-code them?
I have this code that will import the excel sheet to the datatable then inserts it in the database, but I have this problem.I have set the HDR to yes so that the first row will be considered as its header, but the problem now is that if the first row is null, the datatable will automatically named it's header as f1,f2 and so on. how can I set the header as null if the first row is null? so I can validate it afterwards
How could I change the column header of the Data Grid to center or right but not left as default? [We are talking 'bout Data Grid here, recently I always receive answers for Data Grid View instead :( ] I just want to re-align the header only, not the whole column. There's another topic discussed bout this already but it's not working in my case. Here is my code:
Public Class Form1 Private Sub DataGrid1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles DataGrid1.Paint
is there a chance that I change the header name of the exported data from gridview. Below is my code and its working fine. my only problem is I can't change the header name
My code
Dim strFilename As String = Now.Date.Month.ToString + Now.Date.Day.ToString + Now.Hour.ToString + Now.Minute.ToString + Now.Second.ToString Response.AddHeader("content-disposition", "attachment;filename=" & strFilename & ".xls")
I'm using the following code to populate a DataGridView with a worksheet. This is working fine, however, I'm unsure how I can get the Text from the page header. (not to be confused with the column header). Later in my code when I am exporting into an existing workbook with a new worksheet, I'm wanting to use the header text as the tab name. The header text being "September 2009" so that when I import/manipulate/export october, the new tab will be "October 2009" etc. [Code]
in my application i created table called houseloading which has field called housename.which is inserted into the sqlserver database. my table will look like this
///column name house values red green
what i want now is i want to display the values red green as column header in datagridview
I realise there is a solution for this but I am struggling to get it to convert to VB correctly.I have managed to get a cascading set of dropdowns with data based upon each others results which I was really pleased with.However due to the post back the grid will disappear until the second value is selected and looks awful.Is there anyway within VB to allow the header to stick around if there is no data within the grid view?
I am importing an excel sheet into my sql database. Everything works fine, but I would like to read the column header in as static value. Not sure how to do this. Here is the code I am using to read the sheet in:
'Connection String to Excel Workbook Dim excelConnectionString As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & MyFile & ";Extended Properties=""Excel 12.0;HDR=Yes;"""
I am trying to read excel data (Excel 2007 SP1, on Windows XP SP3) with visual basic .net 2008 (VB 9.0 SP1). I have tried several attempts and whatever I do I am getting the following error message: System.Runtime.InteropServices.COMException was unhandled ErrorCode=-2147319784 Message="Altes Format oder ungültige Typbibliothek. (Exception from HRESULT: 0x80028018 (TYPE_E_INVDATAREAD))" Source="Microsoft.Office.Interop.Excel" Message="Altes Format oder ungültige Typbibliothek." Translated: Old format or unknown type libraryI have added the reference "Microsoft Excel 12.0 Object Library" to my project. I am assuming that I might have to add a different or an additional reference, but I do not have any clue which one to use. List of things I have already done:- Searched other forums- Altered the language settings- Tried it on an other Computer (Win XP SP3, Excel 2007, Visual Basic 2008 Express)- Ran the diagnostics tool in Excel - Updated all updates etc...- Reinstalled Visual BasicI really do not have any clue why it should not work?
Imports excel = Microsoft.Office.Interop.Excel Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim xlsApp As excel.Application
It seems that on clicking datagridview column header, the column will be automatically sorted based on the column type. I have a column showing some numbers. If column type is string, it sorts "1","20","3" into "1","20","3". If column type is double, it sorts into "1","3","20" which is the result that I want. However, there might be some erros in the numbers and error messages(text) will show in the cell instead of numbers. So I cannot set the column type as double. I want to ignore these error messages and sort all the numbers. How can I do this?
Also, I need to add some background colors to different rows in datagridview. So in the column header click event, I call the bkgColor Sub to achieve this. My question is that how can I override the sorting method in this event?
Private Sub DataGridView1_ColumnHeaderMouseClick(sender As Object, e As System.Windows.Forms.DataGridViewCellMouseEventArgs) Handles DataGridView1.ColumnHeaderMouseClick Try
