On a button click I need to test whether or not an array has been filled, if it has the user gets linked to a new form otherwise they receive a message box telling them to first assign values to the array.
I've tried 'If MyArray Is Nothing Then....' and 'If MyArray.Length < 1 Then...' but neither seemed to have worked.
I have an array set up to receive the names of forms when they open. The form name is sent as a Form not a String therefore when I run my code I cannot check for whether the field is empty in the normal way (ie. array(1) = "") as the "" are only usable with strings!
Dim Forms(24) As Form
Dim i As Integer
Dim Free As Integer = -1
[CODE]...
I only need a solution to do the same as array(1)="" but for windows forms.
A really boring question, sorry, but I really don't know that yet ;) I've tryed always string.empty, but with a decimal, there is an error.
View 3 Replies[code]... Check Datagrid Is Empty?
View 1 Repliesi have a dataset that takes results from a select to a sql database. the select returns rows and sometimes returns no rows. how can i check if the dataset has no rows from the select? [Code]
View 4 RepliesI need to check if a .txt file is empty, if it's not, the code will read the file and process the information.I know how to read .txt file. Is there a way to check if the .txt file is empty? not an empty line just completely empty?
View 3 RepliesI was wondering how to check if a list box is not empty I have inserted my code I want t check if there if text in the listbox and if there is no text do some thing. I have put the line of code i am having trouble with in red
result = MsgBox("Are you sure you wish to make the required number of lockers", MsgBoxStyle.YesNo, "Confirm Order")
If (result = MsgBoxResult.Yes) Then
CheckLevels()
If lstOrder.NoItems = True Then
[Code]...
I've done an internet search to determine if I can detail if a SQLDataAdapter is empty after running an SQLCommand? My research so far point I can't check if the SQL dataAdapter is empty until I bind it to a dataset/datatable. Ideally would not like to run another SQL command to do a row count to determine if query retruns rows or not. I'm populating a datagridview and would like to alert the user that there is no data to view. What's the most efficent way to check if an SQLDataAdapter is empty?
View 4 Repliesi want to insert the data into the table only if the table is empty, so for that i need to check the condition to check whether data already exists in the table, if present then i want to empty the table before inserting the the fresh value.
i know how to insert and delete the data only prob is to check the condition. so please can any help me out in this.
TO INSERT
Dim comUserSelect As OleDbCommand
myDateTime(i) = DateTime.Parse(arr_dateTime(i))
' Console.WriteLine(r("P1"))
[Code].....
In Visual Basic 2010 I have a PictureBox control which i need to check in code to see if it does not contain an image.
View 2 RepliesHow to test the stacks if it is already empty? I tried Stacks.IsEmpty but unfortunately I have an error says:
IsEmpty is not declared..
Is there any way to test if the stack is empty? When I'm typing (after dot) there is no IsEmpty properties of the stack.
Possible Duplicate: Checking for an SQL result in VB.NET
I have login form which is redirect user for their levels but before to that if there is no any user on the data table I would like to redirect to create admin form. I have all the forms but I didn't manage to redirect them because I don't know how to create statement.
Dim con As SqlCeConnection
Dim command As SqlCeCommand
con = New SqlCeConnection("Persist Security Info=False;Data Source=.database.sdf;Password=********;File Mode=shared read")
con.Open()
[Code] .....
I have this code is working. What to write for
Private Sub frmlogin_Load(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles MyBase.Load
End Sub
Here is my problem-> I have three folders that I need to check if they are empty or not, if one of them is empty, I would like to keep checking the other two, if they are not empty I want to do something and then check the other two, but not all the time all three will be empty or not empty there might be times where one folder has something and the other two not and so on. I just want to check a folder and if its empty go to the next one but if not do something and still g to the next one to check if it empty or not, an so on.
View 3 RepliesIve got a Form application in VB.NET.I have many text boxes on one form (about 20). Is there anyway to check them all at once to see if they are empty instead of writing out a massive line of code to check each one individually such as
If txt1.text = "" Or txt2.text="" Then
msgbox("Please fill in all boxes")
i want to check the table column null or empty......in vb.net iam using ms access in backend.....
View 2 RepliesI have a code in Save Button, and part of it, a code that checks if the dynamic text boxes that has been created is empty. But when the system runs, it only check the first set of text box and an an message appears "Collection was Modified; enumareation operation may not execute.".
Here's the code:
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
Try
For Each txt As TextBox In TextBoxes2
If String.IsNullOrEmpty(txt.Text) Then
[Code]...
I'm trying to retrieve some data from an Excel with the following [code]...
At some point the Recordset encounters an empty cell which it can't assign as a to Recordset.Fields("BG").Value. VB2010 will then throw an error: When casting from a number, the value must be a number less than infinity.
correct syntax for checking on an empty cell?
How can i check if a string collection is empty? I tried
VB.NET
My.Settings.IPBank.Count = 0
But it said
Quote:
Object reference not set to an instance of an object.
First time poster and new to ASP programming.I have a functional database to where i am trying to add new functionality.I'm trying to add the idea to check if a returned string is empty, if so get value from a backup table which holds historical information. Here is what i have got for the specific part:
[Code]...
I have a mask of : 00/00/0000
I need to check if the masked text box is empty,I tried MaskedTextBox1.Text
it returns --/--/--
How can I check whether the user has entered a value to the maskedTextBox or not?
I am getting product id value some times null and empty from databasehere how i check if valule null and empty
productid = IIf(IsDBNull(TempDT.Rows(0).Item("productid")) =
True,
"", TempDT.Rows(0).Item("productid"))
[code].....
I have numerous textboxes which I use to gather data to be placed into an array. But I want to ensure, before I place them to the array,that there is at least one character (letter or number, no space) in each textbox. Seeing as I have about two dozen, it would seem tedious to write an If...Then statement for each of them. And I cannot use a custom textbox class for this. So how can this be done?
View 3 RepliesI've used System.IO to check if files exists/copy/delete in the past but I have not been able to check if the file is empty?
I have two text files, and i want to add a check to see if both files are empty, if they are empty then I want to exit the application.
im getting a image from my database to a data set. before i convert it to a proper picture i need to check whether ds.Tables("userDetails").Rows(0).Item("photo") is EMPTY or NOT. How should i write the if condition? <code>If ds.Tables("userDetails").Rows(0).Item("photo")<> ??? Then
Dim pictureData As Byte() = DirectCast(ds.Tables("userDetails").Rows(0).Item("photo"), Byte())
Dim picture As Image = Nothing
Using stream As New IO.MemoryStream(pictureData)
picture = Image.FromStream(stream)
End Using
[Code]...
I am using VB.net to create a simple winform. I have the option to save the data I input on that form. I am trying to prevent the user not to save the data if textbox10 is empty. I tried the while loop but I go into an infinite loop. The code is below. The if statement gives the error but allows the user to save.
[Code]...
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 RepliesThe code below works fine as long as there are values within an XML node (For example the <CPU>Intel</CPU> node below) but it throws an Exception error when the node value is blank/null whatever as in the example node <Monitor> </Monitor>.t's ok if the node value is blank, I just want to check for it and not throw an exception error.This question uses the following XML snippet below: Note: The tag <Monitor></Monitor> has no value in it.
<PCSettings>
<SystemSettings>
<CPU>Intel</CPU>
[code].....
I have some application settings that I want to put some error checking in and the below code does not work.
If My.Settings.SmtpServer = ("") Then
MsgBox("SMTP cannot be blank!", vbExclamation, "SMTP App")
End If
What is the best way to checkt o see if the TelephoneNumber property has some string in it that does not Trim down to an empty string? I hate to use the Trim VB.NET function on Nothing just to give me an empty string whenever the TelephoneNumber is Nothing. [code] What puzzles me is that the "IsNullOrEmpty" function works as an extension method of a string instance even if the String is NOTHING. Why does this extension method work but the follow straight - .NET code raise an exception? [code]
View 4 Replies