new with Linq and very excited with this feature. However, I want to see if I can do the following with LINQ:
[code]...
Notice that I have a break in my foreach loop, meaning that I just need to reset the first match row's column value to empty string.
i'm trying to get my program to look up a string and find a match in an access database in column "PhoneNumber" and return the value from column "FullName" on the same row to a different string
so it would go like this: (i really don't know much about accessing databases)
Dim PhoneNumber As String
Dim FullName As String
PhoneNumber = TextBox1.Text
FullName =
I need to sort a DataTable or DataGridView by a column that is a string value, but with null/empty values at the BOTTOM when sorting ASCENDING. The DataTable is NOT populated by a SQL statement, so no order by. If I do
[Code]...
I need to sort a DataTable or DataGridView by a column that is a string value, but with null/empty values at the BOTTOM when sorting ASCENDING.The DataTable is NOT populated by a SQL statement, so no order by.If I doDataGridView1.Sort(New RowComparer(System.ComponentModel.ListSortDirection.Ascending))then it throws an exception, saying that the DataGridView is DataBound, which is correct, but doesn't help me, and I want to keep it databound.
View 2 RepliesWhile writing an app that uses a couple settings, they occasionally get re-set to empty. I haven't seen any pattern to this, but I do have a vague memory that there are certain circumstances that will reset the settings in a project under development. What are the circumstances that cause the settings to be reset?
View 6 RepliesThis must've have been asked before but I couldn't locate it. In a mixed code project (VB and C#) we were debugging some old Visual Basic code where a statement as follows could be found:
If Request.Params("xxx") <> "" Then
'do something
I considered this a bug as Request.Params could be null, in which case the statement would've become false which wasn't the idea. So I thought. I just found out, -- probably for the tenth time and I will keep forgetting -- that the following two statements are not equal, while Nothing in VB should be equal to null in C# (thought I):
if(String.Empty == null) // always false
If String.Empty = Nothing Then ' always true
Should I dismiss this as a typical Microsoft backward compatibility effort, or should I consider this a huge error in the VB.NET compiler? Does anybody know the Microsoftean opinion on this oddity?
Using VB.Net If the grid cell value is empty, i am getting error as "Conversion from string "" to type 'Double' is not valid"Code (gridview_CellLeave)
Dim z1, z2, z3, z4 As Int32
If grvList.CurrentRow.Cells(1).Value <> "" Then
z1 = grvList.CurrentRow.Cells(1).Value
End If
If grvList.CurrentRow.Cells(2).Value <> "" Then
[Code]...
I have a array of strings and I am looping through them, but the string might be empty so I am trying this:
[Code]...
I was wondering how i could pass the following SLQ function to my datatable:
Select sum(Quantity) from Purchases where transaction_mode=1
The count of column names and source expressions do not match. [ Column name count = 20,Source expression count = 19 ]
View 5 RepliesWhat code is needed to auto-size columns to match the width of the widest text?[code]...
View 6 RepliesI have a form in an application that I'm building that shows a datagridview with the last field being a checkbox. What I'm attempting to do is if the user clicks on the checkbox and then clicking on "Save Changes" all of the fields on that datagridview row (except the first field) is then saved to a database. I have the following [Code] The error I keep getting is "Insert Error: Column name or number of supplied values does not match table definition.".
View 5 RepliesThe database field has text inside the field and I want to match it with another string...How do I convert a field to a string?
View 7 RepliesIm trying to work out what the best way to match 2 strings together, but with a difference.
String1 = "dog cat bird chair book table"
String2 = "the dog chassed the cat around the chair"
No I know I can break string1 up by space character and check if each word appears in string 2, I would prefer to not have to do that.If there some sought of regex that would take a group of words and retrun how many of them matched ?
I have a form in an application that I'm building that shows a datagridview with the last field being a checkbox. What I'm attempting to do is if the user clicks on the checkbox and then clicking on "Save Changes" all of the fields on that datagridview row (except the first field) is then saved to a database. I have the following
Private Sub holidaysaveButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles holidaysaveButton.Click
For Each dr As DataGridViewRow In DataGridView1.Rows
[Code].....
i want to check the table column null or empty......in vb.net iam using ms access in backend.....
View 2 Repliesis there a way to show in datagrid only those row that has column that is empty, im using this code
Me.DataGridView1.DataSource = ds.Tables("0").Copy() but it shows all the data from my table.
What is the best datagridview event to use these codes I want to check column 0 is empty or has some value
If e.ColumnIndex = 0 Then
If DataGridView1.CurrentCell.Value = "" Then
MsgBox("Empty Value")
[code]....
Hi, Is there any way to check which row of the value(any of the Column) is empty and get the row number??
View 4 RepliesI am trying to get this to iterate and append the items in my listbox, which are single column excel files into a single sheet. However, for some reason its placing my second data set out in the bottom of the sheet. I feel like I'm probably missing something very basic here and I've been looking at for to long this afternoon. I used to create this worked splendidly in some other applications I've been developing.
vb version is 2008 VB express excel version is 10.0
Code:
For Each filename In ListBox3.Items
If System.IO.File.Exists(filename) = True Then
xlBook = CType(xlApp.Workbooks.Open(filename), Excel.Workbook)
[Code].....
I am using TextFieldParser to Read a Tab Delimited Text DataFile. The problem I have is that some times the data file (3rd party provided) contains an extra Tab which therefore creates an extra column. I need to remove this unnecessary column. Some columns will have rows that are empty so I cant just delete the column if it has a blank row, So I think I need to loop through each column and if if every row is blacnk then delete that column.
Here is the code that reads the file, I was going to remove the column from the table called table before I populate the table called dtAll , which is what my program uses
Dim safeFileName As String = IO.Path.GetFileName(Me.OpenFileDialog1.FileName)
Using myReader As New Microsoft.VisualBasic.FileIO.TextFieldParser(safeFileName)
myReader.SetDelimiters(vbTab)
Dim currentRow As String()
[Code] .....
Ok i have a weird issue. I cant figure out what to use... CSV has two colums :-Name, MobileJohn Doe,60002000Jane Doe,Now i would like to delete the whole line if mobile number is empty.. i cant figure out what to use. Mobile number are 8 digits long.
View 11 RepliesI was trying to call a method using Reflection on a method that has a STRING parameter.However a STRING does not have a parameterless constructor.So instead of something like.>>
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
[code].....
i have a string array that i want to output to a text file. the array size is 10000. i fill the array starting from 0 with some strings. at the end, i only want to show the array from index 256 to the last array that is not empty (for eg. if the array is filled with data from 0 to 2000, i only want the text file to show the data from 256 to 2000 and ignore the remaining strings). Is there any function to do this?t i use is shown below
Dim myArray(10000) as string
Dim strArray As New System.IO.StreamWriter("c:List.txt")
strArray.WriteLine("{0,10}{1,30}", "Index", "Symbol")
[code].....
I have :
[Code]...
I think I have explained my problem properly..
I'm currently trying to match a word in a string - to a word in an 1 dimensional arrray.
So it does this.
1.Goes into array, gets first word.
2.Looks for that word in the string.
3.If can't find it, go to next word in array.
4.And so forth until it finds it or runs out of words in array.
Problem is the string can be upto 2000 characters long. And the Array with the possible matches can have upto 8000 entries.
So when it runs, if the word begins with 'A' it finds it dead quick as the 'A's are at the top of the array, ordered alphabetically. This is great.
But if the word starts with 'Z' then it takes 4-5 seconds before finding it.
I'm basically using InStr to find the word in the string.
how to check if the user input has a match in my given string
Dim a as string
a = "abc"
if the user input in the textbox "erty" the message box will be shown string not found. if the user input 123abc the message box will be string found
I got on my form textboxes, checboxes but also a groupbox which holds texboxes.
The idea is to be able to clear and reset all of these by clicking a reset button.
At the moment i got this
Private Sub ClearFields()
Dim ctrl As Control
[Code].....
But ofc Me.controls isn't gonna get involved with the stuff in the groupbox.
My requirement is to read all rows of an excel-sheet in first column that are not empty, are numeric and have a length between 15 and 20.
For example:
358218033354974
359473035499561
358218036156129
354022038366247
358218032490035
359473030516492
353210040325399
This column might have a header that is not numeric and there might be empty rows. This would cause an exception when importing them via SqlBulkCopy. So i want to prefilter the correct rows via OleDbCommand.
What I have tried so far is following(C# is also appreciated):
Using connection As New OleDbConnection(sExcelConnectionString)
connection.Open()
Dim schemaTable As DataTable = _
connection.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, _
New Object() {Nothing, Nothing, Nothing, "TABLE"})
[Code] .....
But this throws an exception if there are empty rows or the format of the value is incorrect. So my question is: How to restrict the rows of OleDbCommand to:
Get only first column of every worksheet
All values that are numeric
Skip empty values
Ideally only the values with a length between 15 and 20
Any way how to skip the empty rows, Or do I have to to select the whole datatable? I hoped it would be possible to do that only with one query because of performance reasons.
I try to hide the radio button if the cell is blank but the radio button still show even the cells is blank. why the radio button will not hide?
Dim temp As String = questionDetails.Rows(3).Cells(1).Text
If temp = "" Then
Option3.Visible = False
[Code].....