only entering numbers

i'm asking the user to enter a number like entering his salary..how can i validate that the user it entering only a number.. to go on with the processes.. like if he enteres anything by mistake..an error message will appear.. but how to do the validation thing here..

waiting..
sarooshAsked:
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bobbit31Connect With a Mentor Commented:
something like

try {

   Integer.parseInt("12345");
   Float.parseFloat("12345.50");

} catch (NumberFormatException nfe) {
   // invalid string
}

0
 
kylarCommented:
If you're using Swing, create a document that doesn't allow the user to enter any non-digit characters and use a JTextField that utilizes your new document.

Kylar
0
 
pv_ramanCommented:
If u are using TextField component,U can add a KeyListener to the text field.for each character verify whether that char is in between 0 and 9.
for eg, ch >=0 && ch <= 9, then only you allow user to enter, otherwise display error message to him.
or
create a document that doesnot allow the user to enter other than digits.Take the constructor of JTextField to utilize ur created document object.or use setDocument()

Hope this will help u.

Raman
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pv_ramanCommented:
If u are using TextField component,U can add a KeyListener to the text field.for each character verify whether that char is in between 0 and 9.
for eg, ch >=0 && ch <= 9, then only you allow user to enter, otherwise display error message to him.
or
create a document that doesnot allow the user to enter other than digits.Take the constructor of JTextField to utilize ur created document object.or use setDocument()

Hope this will help u.

Raman
0
 
dyma82Commented:
bobbit31's is the most suitable solution!
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saurav17Commented:

Hi saroosh,

Hope u could do that with isNan().


Regards,
K.J.S.
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Venci75Commented:
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:
Answered by: bobbit31
Please leave any comments here within the next seven days.
 
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Venci75
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NetminderCommented:
Per recommendation, force-accepted.

Netminder
EE Admin
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