C# - Work Around For PrimativeType.TryParse?
Aug 21, 2009
I have become accustomed to using TryParse for attempting to parse unknown types:
Dim b As Boolean
Dim qVal As Boolean = If(Boolean.TryParse(Request.QueryString("q").Trim(), b), b, False)
or
bool b;
bool qVal = (Boolean.TryParse(Request.QueryString("q").Trim(), out b) ? b : false;
So, just curious if someone knows a better way of doing this other than using a ternary operator.
public static class PrimitiveType
{
/// This function will return a parsed value of the generic type specified.
/// </summary>
[code]....
Just pass in the type you're expecting as the generic and provide a string value to be parsed and a default value in case the string is not parsable. If you provide a class instead of a primitive type it will throw new ArgumentException("Generic type must be a valid Value Type that has a Parse method.");
View 3 Replies
ADVERTISEMENT
Dec 17, 2009
I am trying to check this app. and make sure only numbers are placed into the textbox, but my tryparse isn't working.
Private Sub btnConvertC_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConvertC.Click
Dim intTemp As Integer 'holds the text input
If Integer.TryParse(txtTemp.Text, intTemp) Then
[code].....
View 4 Replies
Dec 11, 2011
I have an array of 5 objects and also 5 textboxes. I am wanting to check to see if the values in the corresponding textbox are valid for the type of object.I have currently hard coded this, I parse out the object type and then use a tryparse statement depending on the object type.
Can I do this automatically? Can I detect the type and use a tryparse statement for that type. Maybe something like:if objectarray(x).tryparse(textbox(x).text, nothing)
View 1 Replies
Nov 3, 2010
The adultcombobox & childcombobox have value from 1 to 10, and none.I try put it in Do Loop like the code below, but the total price not come up so well, so I think I am having problem with the Do Loop and the Payment method.One more thing, do I need to Tryparse the combobox and use the selectedIndex ?
[Code]...
View 2 Replies
Nov 8, 2010
I am in my programming class and we had a small program to make that would check to see if an value that was entered is a integer and convert it to a Roman numeral. I know how to properly do it by putting the TryParse into the If...Then statement. What I am trying to do is to not use an If...Then statement and go just by a Case Selection statement. If it is not possible then that is cool with me, I am just trying to think outside the box. Here is what i have done with it:
[code]....
When you do say "Case 1" it says it needs to be "Case CBool(1)." Using either "Case CBool(1)" or "Case 1 = 1" provides the same result .However the code shows no errors it doesn't do the conversion, it always displays the label's value as "I"
View 3 Replies
Jan 26, 2012
this is for homework but I have 90% of the project done, I just need to finish the data validation portion of the code. This is what I have for the calculate click event:
[Code]...
View 3 Replies
Feb 12, 2012
this is for homework but I have 90% of the project done, I just need to finish the data validation portion of the code.This is what I have for the calculate click event:
Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
Dim intInputA As Integer
Dim intInputB As Integer
Dim intInputC As Integer
[code]....
My Problem: I am using the Try parse to validate weather the inputA(B)(C) is an integer or not, if it is an integer, i want it to move to the nested if and validate that it is a positive number, and show the error message in the label if it is not. If it is not a number at all i want it to show another message in the label. The problem that I am getting is that even if i put in a letter for the input it does not catch it and it continues on to the select case, which comes out 0.
View 14 Replies
Jul 3, 2009
My understanding of the Integer.TryParse() function was that it tried to parse an integer from the passed in string and if the parse failed the result integer would remain as it did before.
I have an integer with a default value of -1 which I would like to remain at -1 if the parse fails. However the Integer.TryParse() function on failing to parse is changing this default value to zero.
Dim defaultValue As Integer = -1
Dim parseSuccess As Boolean = Integer.TryParse("", defaultValue)
Debug.Print("defaultValue {0}", defaultValue)
Debug.Print("parseSuccess {0}", parseSuccess)
[Code]....
View 2 Replies
Oct 11, 2009
On all my assignments I am asked to make sure the data is valid - only numeric, no empty strings. And I keep wondering which is the best to use IsNumeric or TryParse. When I try both on coding they seem to do the same thing, and I don't seem to find my answer online. Any ideas of why to use one over the other.
View 3 Replies
Mar 28, 2010
I am creating a program that will convert Celsius to Fahrenheit and visa versa. The program must use a function to return the answer. I'm using a string function that will return either the temperature in Celsius or Fahrenheit or "Please enter a valid temperature" if anything but a number is entered. TryParse is used to check if the input is valid.
When using the TryParse method in the function I am trying to use a parameter to pass the variable that will store the converted data type value [Code] The line " If Double.TryParse(tempTextBox.Text, scale) Then " is supposed to check if the conversion is possible and if it is pass either F or C as a variable to the scale parameter. It seems to verify the conversion all right but it doesn't actually do the conversion. Why isn't doing the conversion? Both F and C remain 0. I can get it to work by using two more TryParse methods (one in each branch of the If else statement in the function), but I'd rather not do this.
View 8 Replies
Dec 7, 2010
With a Decimal, I use:
document.Air1 = CDec(IIf(Decimal.TryParse(Air1TextBox.Text, Nothing), Air1TextBox.Text, "0")) to fill the column with there is no value.
I would like to do something similar when the date is blank (preferably with NULL or just plain blank):
document.TestDate1 = CDate(IIf(Date.TryParse(TestDate1TextBox.Text, Nothing), TestDate1TextBox.Text, " - - ")) - of course, this throws an exception.
The table Data Type is date.
View 3 Replies
Nov 9, 2009
Is there any way to use the TryParse method to check for letter text input?For example, a user needs to input a name in a text box. Is there anyway to check that input are all letters?
View 4 Replies
Mar 10, 2009
The code performs correctly when the input is an integer, but when I enter a character, the result is as though I've entered an integer. Can you tell me what's wrong with my TryParse statement?
Private Sub btnCompare_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCompare.Click
' Declare Local Variables
[CODE]...
View 2 Replies
Oct 21, 2009
How would I code a TryParse to get the input from customer from a textbox named Strands and convert it to a number (this number will always be a whole complete number, cannot be 5.6 or 4 1/2 or whatever) then have that Strand number be muliplied by the selected item in my listbox1. This listbox has an access database bound to it with 2 columns Size and Area, the Size equals the Area and I set the Value to the Area column but set the Size to show up in the list box. and the Strands textbox has to muliply by the Size picked, but by the Area # not the Size #. And the results of that multiplication showing up in another textbox named total.
View 14 Replies
Dec 22, 2010
I have a TextBox in a Windows Forms application in VB 2008 (.NET 3.5) where a user can key an estimate amount. I am allowing them to key dollars and cents, and I want to round to the nearest dollar. The original code had the rounding down when the data was written back to a table, and that worked fine - I have this code in a "Save" routine that fires when the user moves to a different screen or record:
Dim est As Decimal : Decimal.TryParse(txtEstimateAmount.Text.Trim, est)
Dim estimatedAmount As Integer = Math.Round(est)
I decided that it might be nice to actually do the rounding as soon as they leave the field instead, so they're not surprised when they reload the screen and find that 1822.60 is now 1823. So I took the exact same code and added it to the TextBox.Leave event handler. And the weirdest thing happened: instead of the variable est being populated with 1822.60 after the parse, it gets set to -1! What the...?
Debugging the handler shows that the value goes into the parser correctly, and if I do the parsing manually via the Immediate window, it parses correctly, but when I let the code do it, it invariably gets set to -1. What's even weirder is that any number gets parsed as -1, not just decimals, and any non-number gets parsed as 0 (which is correct).
Has anybody else ever run into this before? I tried moving the code to the TextBox.LostFocus event instead, but with the same results. I have no idea what in the heck is going on, and obviously there are workarounds galore for this, but it just makes no sense whatsoever.
EDIT: Here's the full event handler (current behavior for which is to put -1 in the TextBox):
Private Sub txtEstimateAmount_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtEstimateAmount.Leave
' Take any dollars-and-cents amount and round to the nearest dollar
Dim est As Decimal
[code]....
View 2 Replies
Jun 16, 2010
I have string that contains "1.3" and I am checking with Date.TryParse method. It automatically converting into "1/3/2010". How to handle this?
View 1 Replies
Oct 6, 2009
I used this quite frequently, but could never define its role
View 5 Replies
Dec 7, 2011
I have Tried to convert "1" to integer using Tryparse it showed true but when I used it on "1.00" it is showing it as false, why?
View 1 Replies
May 29, 2012
I found that when group by multiple values does not work well with VB.NET, but it works well with C# ,here are my code, is there something wrong with my VB.NET Code? Here is my VB.NET code:
[Code]...
View 1 Replies
Feb 2, 2011
I have an application that requires data be entered, and after entering, a button is clicked to process that data. Clicking the button works just as it should--the data is processed properly. In constructing a test module, I provide a set of data values, followed by:
btnWhatever.PerformClick()
Nothing happens. I have used this syntax for years, and it has always worked flawlessly. I have triple checked everything else and isolated the problem to the failure of the PerformClick(). The PerformClick() is in a test subroutine that does nothing but fill textboxes and labels with default data, then calls the PerformClick() on the button to begin processing. Again, the button works fine, the data is entered as it should be, but the PerformClick() does not fire the click event.
View 21 Replies
Aug 21, 2009
I have a form that works on my local Machine I created into. I have Office 2007 on this machine. I created the Form with the Excel 12 Reference. I move the Entire conetence of the Project folder to my work computer. Which has Office 2003. Do I need to recreate the form with the Excel 11 reference. I could not get the form to work on work computer. IT has a com error. I am acessing the EXE for the debug folder w/in the Bin Folder.
View 7 Replies
Jul 25, 2010
will SQL statements that work in Compact SQL Server also work in the Express Edition of SQL Server?
View 2 Replies
Jul 21, 2010
Dim pc As PrincipalContext = New PrincipalContext(ContextType.Domain, GetPath) ADUserInfo.PasswordVaild = pc.ValidateCredentials(LoginName, Password)
View 1 Replies
Oct 19, 2011
I'm using vb2008 with DB MSA2007 (save it to MSA2003) on Seven(7)System After I create my project I build it(make exe). then I took the file of project (application) and the DB from Debug Folder.
I tried to run this application with DB on another computer it's system is seven and MSA2007 and work very well. then I run it on pc it's system XP and MSA2003. it showed this error
Application Error THE APPLICATION FAILED TO INTIALIZE PROPERLY (0XC000135). Click on OK to terminate the application
View 1 Replies
Jan 8, 2012
I'm building a VB(2010) program to create the graphics for my laserprojector.The program works when I debug it in VB, but when I run the EXE program in the release directory, it doesn't work. The problem in the EXE program is theat I can't draw/view graphics in the picturebox..I coppied my whole program to a new VB project, but I'm having the same problem...In the original project, where the program works, there are no warnings or errors.
View 3 Replies
Mar 28, 2011
I created a windows form application using Visual Basic Express Edition 2008 but I did not know I could not use it on the web, which is what I wanted but being new to VB I just got a lot of headaches trying to figure this out. It works fine as a windows app but now just recently I installed Visual Web Developer 2005 to so I could create a web application from the windows app.
It is a simple windows application of a datagrid but now I want to run the same design application I made in Visual Basic to Visual Web Developer Express 2005. Is this possible? And, what do I need to do? I have all of the associated files in my project folder in Visual Basic Express folder.
View 1 Replies
Mar 14, 2011
how does look-up work in Visual Basic, I have done research on this but it does not explain. I have a Form1 called( Booking form) with 2 ComboBox's and 1 TextBox. each called (Destination_FromComboBox) and (Destination_ToComboBox) and (FareTextBox)and another form2 called (Fares Form) with 3 TextBox's each called TextBox1 (FromTextBox), TextBox2 (ToTextBox2), TextBox3(FareTextBox).So when I select (Booking Form) and Insert or select a Destination from (Destination_FromComboBox) and Insert or select a Destination To (Destination_ToComboBox) I want to read from (Fare Form/Fare Table) and give me the fare in FareTextBox on the Booking Form. Also on the booking I have 3 Radio Buttons
(RadioButton1 = 4 Seater Car, Normal Fare)
(RadioButton2 = 6 Seater Car, Time & HalfFare)
(RadioButton3 = 8 Seater Car, Double Fare)
But there is also a time Issue as well:
If the time is Between 05:00 & 23:59 then normal time should be used
If the time is Between 00:00 & 02:00 then time & half should be used
If the time is Between 02:00 & 05:00 then Double time should be used
I have watched loads of video's and looked through forums and other codes for the combination of the above, without success?
View 5 Replies
Oct 19, 2009
I have this great way to use VB6 I treated my project like a .exe file.Say I want to work on c:work directory.I just save as the .vbp file to c:work directory
All the other files (.frm,.bas,.cls) files are in a special directory called library ALL of my .vbp files, in c:work1, c:work2, c:work3 refer to that one same directory.How can I do that in vb.net?
Why this is important? Bugs always happen all the time. If I just run .exe file, when bug happen, I cannot do a thing. However, if I run the project file and run the program in debug mode, when bug happen I can figure out what happen.
View 9 Replies
Jan 23, 2010
I am a CS grad, but haven't had much to do with programming since my school days as I went the BA route.Anyways, there are a few things that I do manually on the computer and thought that I could probably save time by creating an application for them.But I'm not really sure how to start.I'd like to be able to keep a history of Completed eBay listing so that I know when the price point is good and when it is too high.I noticed that eBay has an RSS feed, so I think I can do it. Just a couple of quick questions:
1 - Can I instruct VB.net to open a web browser and read an RSS feed, or would I need to manually do this myself and then run the application?
2 - What is the best way to work with RSS feeds? Should I convert the data into XML first?
View 2 Replies
May 23, 2010
I am trying to get a percentage that just does not seem to work.I am using WMI to get the Total Physical memory of my system and then the Free Physical Memory. Then get the percentage.
2147483648 - Total Memory
838028 - Free memory
According to Task Manager my physical memory is 59%. This is the code I am using but I can not get 59% or 41% that is free.
temp = FM/TM
temp = temp * 100
percent = FM * temp
View 5 Replies