Restricting user to entering negative and special characters into field

[Sumanth16]

I am using this client script to restrict entering negative value and special characters into field,

1) When user enters negative value into field it is populating alert window ,when user clicks ok it setting field value to blank.But I need to set field value to previous value.

function onChange(control, oldValue, newValue, isLoading, isTemplate) {
if (isLoading || newValue === '') {
return;
}

var specialCharRegex = /^[0-9].*$/;
if(!specialCharRegex.test(newValue)){
alert('please do not enter negative value and special characters into field');
g_form.setValue('field','');

}
}

Thanks in Advance

[SanjivMeher · Accepted solution]

Try this

function onChange(control, oldValue, newValue, isLoading, isTemplate) {
if (isLoading || newValue === '') {
return;
}

var specialCharRegex = /^[0-9].*$/;
if(!specialCharRegex.test(newValue)){
alert('please do not enter negative value and special characters into field');
g_form.setValue('field',oldValue);

}
}

[Sumanth16]

Hi Sanjiv,

Thanks for your response.It is not working ,the field value is setting to blank only.

[Mark Stanger]

FYI.  'oldValue' will always be the value set in the field when the form loads.  If the field is empty when the form loads, you would always end up with a blank field with this script.

[SanjivMeher]

In that case, I would also add this script to onSubmit script and not clear the field on onChange. And not allow the user to submit. User can then manually change it and wont loose what he has entered.