Way To Limit A Textbox To Numbers And "-" (no Maskedtextbox Wanted)?
Apr 24, 2011
yeah im very far with the project right now just a day or two probably of completely finish it, but im so far that itll break alot of things if i change a textbox i have for a maskedtextbox, besides there are some things that the normal textbox does a bit differently than maskedtextbox, ive searched around the net and found nothing about this in vb express, probably because everyone uses maskedtextboxes instead xD
i have one more issues, and hope is the last for now. How can I limit a textboxe's input to only numerical with certain range of values (eg -10 to 10) and with that happening while I type in the values?
I want to control a textbox to only allow numbers, backspace and a certain length. Ive tried with the IsNumeric function but I cant seem to get it to work.
I have a maskedtextbox that i want to limit character input in it but i can't manage to figure it out.The date type is "yyyy-mm-dd" and the mask is "1300/00/00" (it is not gregorian calender, it is persian )In the TextChanged event i am changing the bindingsource filter.Because of this i don't want the user enters invalid date. For example the user enters 9 in here : "1300/90/00" i want to prevent this from happening before TextChanged event occur. (the place isn't important i just want to stop user from entering an invalid month or day)I have tried the KeyPress event but i don't know how to detect where in the textbox user is entering a character.
Note that i know already how to validate and i have a code for that but the TypeValidationCompleted event occur when user does all changes and leave the textbox.
how can i code this?e.g : at the runtime, when i write "hello" into textbox , that text will be red color ,how to code this ?(only "hello" will be red color, other writing will not be red in text )
how to limit number into 2 decimal places sample when i got number of 1000.7585545 is should be 1000.76 i have this code below but based on the given sample it will result to 1001.00
If txtpassPrice.Text <> "" Then Dim dblTranspo As Double dblTranspo = txtpassPrice.Text txtpassPrice.Text = Format(dblTranspo, "#,##0.00") End If
i tried this one but i will result to 1001 only
If txtpassPrice.Text <> "" Then Dim dblTranspo As Double dblTranspo = txtpassPrice.Text txtpassPrice.Text = Format(dblTranspo, "#,##0.##") End If
I'm trying to limit the number of decimal values to 3 in numbers such as .3125 but I also have numbers such as .5 which I need to leave as is.
how can I determine if a number is 4 decimal places and cut off the last number.. I don't want to round up either.. .3125 should be .312 not .313 and .5 should stay at .5 and not .500.
After experimenting around with DevExpress controls and adding them to my form, Custom mask do not seem to work on the MaskedTextBox. If I place a custom mask and debug, I get a null reference exception.
It seems to be the maskedTextBox's mask property that is doing this. I have tried setting the mask through design and by code. However, neither way works.
My question is, is it possible to use a TextBox as a maskedTextbox? To be able to format it? I need the user to enter in hours, minutes, seconds like hh:mm:ss or 00:00:00.
Here's the error I get:
"NullReferenceException was unhandled. Object reference not set to an instance of an object."
The tricky part here is, whenever the decimal sign key is pressed, the input procedure understands that the following number is to be displayed to the right of the decimal point (not left).
Now, I'm trying to do this in VB. Unfortunately, my all attempts failed with MaskedTextBox.
Do I have to hardcode this procedure in my program, or is there an easier way to get around this?
i have a form in design view. with faremaskedtextbox and a extra_farecombobox,could anyoneplease tell me the vb code to addfaremaskedtextbox +extra_farecombobox together anddisplay result in another total_faremaskedtextbox.so basically i wanttotal_faremaskedtextbox to add the two numbers that are put into each faremaskedtextbox and extra_farecombobox. and show the result in total_faremaskedtextbox.
I have an officecharge textbox in which I specify how much I'm charging the customer for a specific service. If the user changes the officecharge value for that customer I would like to keep track of the previous value to then compare
it to the new value to then set a boolean variable true or false accordingly. I would like to fire/trigger this segment of code everytime the user leaves the OfficeChargeTextBox (after it loses focus) so that it can compare the final value entered with the previous value and then decide what to do based on whatever login.applies from that point forward.[code...]
I wanted to set a maximum limit of characters of textbox in the properties but i can't find where it is located unlike in vb 6.0 you can set the characters in maxlength...
i would like to limit a textbox input to 20 characters and only one line to input the characters.. i really have no idea where to start. i did see some forum threads, except they're for different options other than the option i need.. trujade.so much work to do and so many choices to choose from...
I want to limit the Textbox to a range of characters in VB. For example, I want the user to enter strings from 5-7 characters. I know how to limit the Textbox to a certain number of characters by MaxLength but that will give him the option of writing just 3 or 4 characters which I don't want to allow that from happening.
So far I have code for a textbox that limits the value entered by a user to two value places. However, I would like to limit the value entered by a user to numerical values only. And to handle any exceptions that go along with it.
I want to limit length in textbox. not total maxlength but maxlength perline. for example. if I choose to limit 7 char per line. when words exceeded 7 in a line textbox will start a newline.(without break the word) can anyone tell how to make it? I did actually search for a long time.[code]although in text "For best results" s is the 8th char in first line.but it;s a word I dont want to break it
Although set textbox width can fit my request.but when writes textbox.text to a file it's actually in one line. for example"Scientists say our ability to focus is being undermined by bursts of information from e-mail and other interruptions. "
is actually one line text.but it shows 2 lines in my textbox. I want when it write to a .txt file it keep what is looks like in textbox. But it's actually one line in textbox. hope I make my question clear.
is there any method to do what I say? what I think is add a Environment.NewLine at each row end. or limit length in textbox. not total maxlength but maxlength perline. for example. if I choose to limit N char per line. when words exceeded N in a line textbox will start a newline.(without break the word) can anyone tell how to make it? I did actually search for a long time.. but I didn't find any useful information for my request.
I just D/L VB express 8, and I'm trying to learn how to use it. what I'm trying to do is write some code that:takes a number into a text box (textbox1.text)do some simple calculations with that number when I press a button (button1)display the results in a second text box 9textbox2.textThe first problem I am having:The numbers are in the "milli" range, meaning to the power of negative three, so 10^-3 = 0.01 I do not want to enter 10^-3 or any other exponent into the textbox, I am simply entering in 10 because all my units will be in milli. I've tried using exponent and scientific notation but it doesn't calculate correctly. I've done a "work around" to get it to do what I want, but there has to be a simpler way to achieve the above results without. for example, the user enters 10 into the textbox, the button multiplies 10^-3 *30, as a crude example, and stroes that value (say, B=10^-3*30) and B is DIM B as Double.
Problem number two:Error checking. I need to validate that only numbers can be entered into the textbox, or else the program will display an error message (messagebox). I can achieve this to some degree with sample code from here and other places, but, some of the code does not take into account that some numbers have decimal places (I have foud code that does, and it does work), but if a users enters, say the letter "E", it crashes the program. If the user enters "10.3Z", it crashes the program. I cannot seem to code for the last case, a mixture of numbers and letters to get an error message box.
I am a new VB programmer and am using TextBox in VB2008. Here are the problems I experienced in TextBox -
1, After I typed number in TextBox and found I need to type another number. So I used backspace key to remove it. But at this time program quit and displayed this problem: InvalidCastException was unhandled. How to solve this issue?
2, Can anybody tell me how to set number of characters are allowed to be typed in TextBox?
3, Can anybody tell me how to implement the feature that only numbers are allowed to be typed? In case letters are typed, how to tell user to re-type?
I am struggling with this code that I Have to do about calculating the nth term of the Fibonacci series. The program is supposed to take the value of n and return the corresponding nth Fibonacci number.If the function is given an invalid n value, it should return -1.