VS 2008 Cast, Convert, ToString - Which One To Use?
Nov 2, 2009
I've been programming in vb.net a lot for the last 9 weeks and I have just come across a lot of double functionalities (hope I used the right word for that).For instance, you can use CInt, CType, Directcast or Convert to turn something into a integer. (Directcast doesn't really belong in that line but whatever).
With calling methods you can do DoWork() or call DoWork()With returning values in functions you can do DoWork() = 3 or return 3 Why is this? Is it just to make the transition frm vb6 to vb.net easier? Or about giving the programmar a lot of options. I must admit I don't really like to have that choice, I am always in doubt whether I am using the right method .
View 11 Replies
ADVERTISEMENT
Nov 21, 2011
I'm just converting a date to a string but I'm getting this error. It's not listed as one of the normal exceptions to the datetime.tostring method. Googling around, it looks like it's an actual bug where it thinks StartDate is an int--but that's no help to me, as I just need to convert the date.
dim StartDate as nullable(of date)
dim Date1 as string
if not StartDate is nothing then
Date1 = StartDate.tostring("yyyy-mm-dd")
end if
View 11 Replies
Aug 19, 2010
I use the expression below to evaluate for a certain value, '91'. If however, the value at that array position is '0B' a System.FormatException is thrown. How do I alter the evaluation so this exception won't be thrown?
View 12 Replies
Jan 4, 2010
I think that my previous post wasn't what I should have been asking. I think my issue has to do with Convert.ToString in my code I have this 3 times, I have no errors while writing the code, only when I debug it I get the error message "input string was not in correct format"
Private Sub DisplayBill()
lblSlicesTotal.Text = Convert.ToString(numofSlice * Slicefee)
lblFriesTotal.Text = Convert.ToString(numo
[code].....
View 5 Replies
Jun 25, 2012
My SQL Server database contains several views which are essentially filtered (WHERE) / ordered (ORDER BY) versions of some of the tables i.e. no joins.
An example would be my Downloads table, which has a view such as DownloadsOnlineOnly e.g.
SELECT * FROM Downloads WHERE Live = 1 ORDER BY FolderName ASC;
I can drag and drop these views onto my LINQ to SQL DataContext, and use LINQ to query these views and retrieve data fine...
But the foreign key relationships are not being picked up in my DataContext, so I've lost the ability to:
Dim dl as DownloadOnlineOnly = (From r in db.DownloadOnlineOnlies Select r).First
Dim fol as Folder = dl.Folder ' Syntax error as there is no association between
' DownloadOnlineOnly and Folder in my DataContext.
I understand why this is happening, but how can I get around this:
Without manually adding associations in my DataContext? Can I change the type of the Entity like changing the return type of an SP on the DataContext? Can I cast or convert between a DownloadOnlineOnly object and Download object? Or some other method?
View 1 Replies
Sep 16, 2009
How do you convert this from c# to vb the ToString function with parameter "c"?
<%= Model.ComputeTotalValue().ToString("c") %>
View 6 Replies
Jul 12, 2011
I am calling a GetSerialNo function But it showing some error like:
Cannot implicitly convert type 'decimal' to 'int'. An explicit conversion exists (are you missing a cast?).
Here is the code:
CODE:
View 3 Replies
Dec 16, 2010
1. What's the difference between ToString and ToString()? (i do know that ToString method is to cast numeric values to string but don't know how to get it to work)
2. Why do i need XML comment feature? is it necessary?
View 3 Replies
Jan 1, 2010
vb.net
Dim stringMessageID3 As New Regex("(?<=<a href=member "" & stringMatches2(i).ToString).*?(?=.htm>)", _
The syntax i have is wrong, i'm trying to append the stringMatches2(i).ToString onto <a href=member i know "&" concatenates but i'm not sure what else i have done wrong.
View 6 Replies
Dec 13, 2011
Just say i have:
vb
Public Class Something
Inherits List(Of String)
[code].....
View 5 Replies
Mar 13, 2011
How would I override the method ToString() for the property CheckBox.Checked?
View 2 Replies
Jun 3, 2009
I read somewhere that older VB .net (pre VB .NET 2005?) couldn't use overloaded operators in a C# class. Is it true for overloaded cast operators?Either way do you guys think it's a disadvantage for a C# class library not to include them and arithmetic methods as actual methods for other languages, like:
ToDouble
ToFloat
FromDouble
Add
[code]....
View 1 Replies
May 22, 2012
I'm trying to solve a problem regarding types of list. First of all I have a stored procedure in my DB which does a select of a single column and I try to proceed it in my app in VB. By making a method function I declared a DataTable that loads through the SqlCommand(with the CloseConnection behavior). After that I publicly declared a List(Of String) which needs to be populated with the rows/items from the stored procedure that is on the way. Below is my snippet of the code:
Dim dt As New DataTable()
Try
If conn.State = ConnectionState.Open Then
[Code]....
It's LPrefix = collection.Cast(Of String)() where I get an exception error telling me that I can't really convert it. The old fashion way is to iterate with for/for each loop but that's not what I want for best use of performance especially if the list will have thousands of rows from a single column. So basically, I want to insert those items from that DataTable to the List(Of String) without For/For Each loop.
Running on VisualStudio2010 Ultimate, .NET FrameWork 4.0.
View 2 Replies
May 18, 2010
Been searching all forums for an answer to this problems for several days now without success.I am trying to Cast/Bind to an HTML Element in an open Internet Explorer 8.0 browser.I need to Cast/Bind to a Frame with a name of "mainFrame".I can get to the Frameset ok but cannot get any further.[code]Can anybody shed any light on how to get HTMLDOC to bind the name part "mainFrame"
View 3 Replies
Oct 26, 2009
I would like to ask some questions related some functions i want to make in my program:
1. I am using this function in order to get a the item code from the database Long.Parse(myReader(0)).ToString("2200000000000") the result i get is: 2200000059091. The form that i want the resultset is
22 (fix value) + item code (6 characters right justified) + 00000 (fix value) 2205909100000 how should i change my code to obtain this result?
2. The programs every time it runs creates a text file which i also attached it plu1.txt, when i try to open it with notepad i see all the lines justified, on the other hand when i open the text file with Wordpad or ConTEXT the lines are not fixed, others are longer others are shorter? What should i change in my code in order to have every line fixed lenght... The code i am using is the following
Dim myReader As SqlDataReader = myCMD.ExecuteReader()
Dim fNextResult As Boolean = True
Using myWriter As IO.StreamWriter = New IO.StreamWriter("c:everest
[CODE]...
3. third and last question is that my program every time it ends show up a pop up menu which says "Text is created." Instead of this i would like to create a file lets say log.txt and every time the program runs, it will overwrite on the log.txt file a line like this: system date + Text is created + with X lines (where X are the lines of the text plu1.txt) ex. 26-10-2009 14:56 Text file created with 15 lines
View 4 Replies
Aug 13, 2009
I have declared two variables as strings strDob and strCurrentDate, Both Variables are for storing dates. StrDob is for storing Date of Birth and second is for Present date. and am executing the following code
If DateValue(strDOB) > DateValue(Date.Today) Then
and getting the error like
Invalid CastException was unhandled
Conversion from string "19/09/1987" to type 'Date' is not valid.
Error in the following code also:
iAge = (CInt(Abs(DateDiff("d", strCurrentDate, strDOB)) / 365))
Invalid CastException was unhandled
Argument 'Date1' cannot be converted to type 'Date'.
Here I need both variables as string itself. because the Dateofbirth is getting from three comboboxes.
View 3 Replies
Feb 9, 2012
Private
Sub cmdExit_Click(ByVal
sender As System.Object,
ByVal e
[code]....
View 3 Replies
Jan 14, 2009
im dr As DataRow = CType(Me.ProductBindingSource.Current, DataRowView).Rowbut I get the error saying:
View 15 Replies
Nov 7, 2009
When executing this code I get this error:
Unable to cast object of type 'System.Windows.Forms.MouseEventArgs' to type 'System.Windows.Forms.DataGridViewCellMouseEventArgs'.
Private Sub NoteGrid_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles NoteGrid.CellContentClick
Try
[code]....
View 10 Replies
Nov 25, 2008
I have no idea how to do this, but I want to create a [I dont know what it is called] to allow me to convert a class property to another type.The I could use the following w/ the new type:
Dim stringPhoneNo as String = "(111)111-1111" Dim typePhoneNo as PhoneNumber = stringPhoneNo.ToPhoneNumber()
View 1 Replies
Oct 8, 2009
When a custom class overrides the ToString() method, the C# IDE uses this function to display the class in the debug mode(tooltips, watcher etc) Does the VB.NET the same? I have impression that overriding ToString() method does change nothing. I mean, in the watcher I see Name myBusinessObjectInsnace Value {MyNamespace.myBusinessObjectInsnaceType}
View 4 Replies
Jan 10, 2011
If you try to compile the query below in Visual Basic .NET, it fails. From x In {1, 2} Select x.ToString() The error given by the compiler is: Range variable name cannot match the name of a member of the 'Object' class. There is nothing wrong with the equivalent C# query, though: from x in new[]{1, 2} select x.ToString()
This does not happen with the ToString overload that takes a format (it is a member of Int32, not Object). It does happen with other members of Object, as long as they don't take an argument: with GetType and GetHashCode it fails; with Equals(object) it compiles.
View 3 Replies
Mar 20, 2012
My problem is that I'm trying to parse a String to a System.Drawing.Color. Im trying to set up a simple notepad, here's part of my code:
Private Sub ToolStripMenuItem6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Colorfuente2.Click
Try
Dim cdlg As New ColorDialog[code].....
View 4 Replies
Feb 22, 2009
I've googled like crazy and tried MSDN but I can't get a clear answer what to use ToString for.
View 11 Replies
Jul 6, 2009
I just converted a VB.net solution into C# solution. But lots of variables have been coverted like:
string var1 = (string)1;
string var2 = (string)intVar; //intVar is a int value
I just want to convert all (string)XXXX to XXXX.ToString() by using some Regular expressions or some other replace methods.
View 6 Replies
Aug 2, 2010
I know that i use a "c" for American Currency is there a ToString value used for Mexican Pesos?
View 2 Replies
Mar 26, 2011
Many times i was not getting correct output,then i put .tostring() at the end then it gave good output.so basically why do v need this?also Convert.ToInt32(cmd.ExecuteScalar()) why convert to int32?
View 1 Replies
Oct 18, 2010
Converting an object .tostring() removes the leading zeros. The object is not a fixed length, so I can't do object.tostring("0000000") where the number of zeros represents the fixed length.
An example object value is "0357" when I convert that object .tostring it becomes "357".
Is there a method for keeping the leading zeros where the length is not known?
View 4 Replies
Apr 25, 2012
Possible Duplicate: C#: why does the string type have a .ToString() method?Why is there a ToString method exist in String class (VB.NET)?
String.ToString()
Will it be a overhead if it is used like
TextBox.Text.ToString()
View 5 Replies
Jan 19, 2012
I just want to know, what exactly the difference between the functions CStr() and Str() and also the .ToString()? With the code provided below, what's the difference between the three?
[Code]...
View 2 Replies
