?
Solved

input string was not in a correct format?

Posted on 2012-04-03
4
Medium Priority
?
417 Views
Last Modified: 2012-08-13
Hi,

I have created an .aspx web page as a front-end form to my db table with the below code for an input field:

<div class="regText">
            <asp:TextBox ID="tbxHowMany" runat="server"></asp:TextBox>
            <asp:CompareValidator ID="cv" runat="server" ControlToValidate="tbxHowMany" Type="Integer" 
             Operator="DataTypeCheck" ErrorMessage="Value must be an integer" />
        </div>

Open in new window


The database field is of type integer and is set to null.

The code behind looks like:

ql.Learners = Convert.ToInt32(tbxHowMany.Text);

Open in new window


The above field is not a required field, hence the null reference. However, upon testing the form the error "input string was not in a correct format" flags on submit. How can I alter my code to allow the form to accept a null value on submit?

Thanks.
0
Comment
Question by:aspnet-scotland
  • 2
4 Comments
 
LVL 28

Accepted Solution

by:
Chinmay Patel earned 2000 total points
ID: 37801463
Hi aspnet-scotland,

Try this

if(!string.IsNullOrEmpty(tbxHowMany.Text))
{
ql.Learners = Convert.ToInt32(tbxHowMany.Text);
}

You may also want to put a validation for numeric input on the Textbox.

Regards,
Chinmay.
0
 

Author Comment

by:aspnet-scotland
ID: 37801502
Do I not already have that validation...

<asp:CompareValidator ID="cv" runat="server" ControlToValidate="tbxHowMany" Type="Integer" 
             Operator="DataTypeCheck" ErrorMessage="Value must be an integer" />

Open in new window

0
 
LVL 28

Expert Comment

by:Chinmay Patel
ID: 37801686
Sorry... my bad... was Tired n Hungry.. :D
0
 
LVL 75

Expert Comment

by:käµfm³d 👽
ID: 37804134
Do I not already have that validation...
No, you do not. Please read up on the CompareValidator. From the linked page:

If the input control is empty, no validation functions are called and validation succeeds. Use a RequiredFieldValidator control to require the user to enter data in the input control.

Also, you have not specified the value to compare against. You should either be targeting a constant value or another input field. You would use a CompareValidator to say, "this field must be less than 5," or "this field must be greater than the value entered in txtSomeOtherValue." You have neither of these.
0

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Calculating holidays and working days is a function that is often needed yet it is not one found within the Framework. This article presents one approach to building a working-day calculator for use in .NET.
Hello there! As a developer I have modified and refactored the unit tests which was written by fellow developers in the past. On the course, I have gone through various misconceptions and technical challenges when it comes to implementation. I would…
In response to a need for security and privacy, and to continue fostering an environment members can turn to for support, solutions, and education, Experts Exchange has created anonymous question capabilities. This new feature is available to our Pr…
Did you know PowerShell can save you time with SaaS platforms? Simply leverage RESTfulAPIs to build your own PowerShell modules. These will kill repetitive tickets and tabs, using the command Invoke-RestMethod. Tune into this webinar to learn how…

569 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question