I am an old developer but new to Objective-C and iPhone development. I am looking for the best way to do form validation for values entered. I have been googling for a while and can't find any good code, but might be using the wrong key worrds, etc... I am looking for things like catching for empty string, numeric validation, date validation, etc... where it catches this either while the user is entering data (input mask type) or on the lost focus of the control.
If you can point me to some good resources that would be great!
Thanks!
Simon.
I don't know particular resources but you could begin usin NSPredicate to validate fields with regular expressions. For example, for mail validation
BOOL result;
NSString* emailRegex = #"[A-Z0-9a-z._%+-]+#[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";
NSPredicate* emailTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", emailRegex];
result = [emailTest evaluateWithObject:anEmailAddress];
The emailRegex suggested by Espuz has a slight problem. The range operator "-" within the [] brackets should be escaped otherwise emails having "-" character are returned as invalid.
I am using the following regex string for pattern matching that allows "_", "-" and "." characters in the address:
NSString *emailRegex = #"[a-zA-Z0-9.\\-_]{2,32}#[a-zA-Z0-9.\\-_]{2,32}\.[A-Za-z]{2,4}";
NSPredicate *regExPredicate =
[NSPredicate predicateWithFormat:#"SELF MATCHES %#", emailRegex];
BOOL validEmail = [regExPredicate evaluateWithObject:txtField.text];
Related
The following example program outputs the same, but the program does not work correctly.
NSDirectoryEnumerator *directoryEnumerator = [[NSFileManager defaultManager]
enumeratorAtPath:kDocdir];
for (NSString *pathi in directoryEnumerator)
{
NSString *fileName_Manager = [pathi lastPathComponent];
NSLog(#"fileName_Manager = %#",fileName_Manager);
Artist *name_Databse = [self.fetchedResultsController
objectAtIndexPath:IndexPath];
NSLog(#"name_Databse = %#",name_Databse.name);
if ([fileName_Manager isEqualToString:name_Databse.name]) {
NSLog(#"Same Name");
}else{
NSLog(#"Different Name");
}
}
Outputs:
2013-04-25 15:37:43.256 Player[36436:907] fileName_Manager = alizée - mèxico - final j'en
2013-04-25 15:37:43.272 Player[36436:907] name_Databse = alizée - mèxico - final j'en
2013-04-25 15:37:44.107 Player[36436:907] Different Name
does not work correctly when special characters in names. Why is this happening?
Thanks ...
have the same problem here:
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"name == %#",[pathi lastPathComponent]];
How do I make an edit here?
The documentation for isEqualToString: suggests you might have a problem:
The comparison uses the canonical representation of strings, which for
a particular string is the length of the string plus the Unicode
characters that make up the string. When this method compares two
strings, if the individual Unicodes are the same, then the strings are
equal, regardless of the backing store. “Literal” when applied to
string comparison means that various Unicode decomposition rules are
not applied and Unicode characters are individually compared. So,
for instance, “Ö” represented as the composed character sequence “O”
and umlaut would not compare equal to “Ö” represented as one Unicode
character.
Try using (NSOrderedSame == [string1 localizedCompare:string2])
Also, if you haven't already, look into the Apple sample code 'International Mountains' which deals with numerous localization issues.
Have you tried converting both strings to UTF-8 and then do the comparison? I don't know if that works, it's just an idea.
I'm really new to ios and i'm trying to write a function that recieves 4 string,
Heres what I try:
this is in my h file:
-(BOOL)validate:(NSString*)fullname:(NSString*)email: NSString username:(NSString*)password
this is in my m file:
-(BOOL)validate:(NSString*)fullname:(NSString*)email: NSString username:(NSString*)password
{
NSString *emailRegex = #"[A-Z0-9A-z._%+- ]+#[A-Za-z0-0.-]+\.[A-Za-z]{2,4}";
NSPredicate *emailTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#",emailRegex];
return YES;
}
the errors is get are that iam using an undeclared identifier
on the emailRegex
and on the emaitTest
Basicly all i'm trying to do is declare a method that recieves 4 strings:
fullname
email
username
password
and implement it.
any help would be good.
good day.
It should be as :
-(BOOL)validateFullName:(NSString*)fullName email:(NSString*)email userName:(NSString*)username withPassword:(NSString*)password;
For Better readability :
-(BOOL)validateFullName:(NSString*)fullName
email:(NSString*)email
userName:(NSString*)username
password:(NSString*)password;
*Edit: Naming convention was not best, so renamed.
I'm making the pattern to check the user can only enter number and string. Please anyone can help me or give some reference. Following is my code. Thnks in advance.
NSString *regEx =
#"(?:[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+(?:\\.[a-z0-9!#$%\\&'*+/=?\\^_`{|}"
#"~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\"
#"x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")#(?:(?:[a-z0-9](?:[a-"
#"z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5"
#"]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-"
#"9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21"
#"-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])";
NSString *strRoadworthyGet=#"vinod123";
NSPredicate *matchPattern =[NSPredicate predicateWithFormat:#"SELF MATCHES %#",regEx];
BOOL resultMatch =[matchPattern evaluateWithObject:strRoadworthyGet];
if(!resultMatch)
NSLog(#"invalid pattern");
You can use NSCharacterSet's alphanumeric method to return check for Letters, Marks and Numbers.
If you want to go for RegularExpression, you can use
NSString *regEx = #"^[a-zA-Z0-9]*$";
Defining legal input characters
I am using the code below to filter the array using the predicate.
self.aPredicateString = [self.aPredicateString stringByAppendingString:[NSString stringWithFormat:#"%# contains[cd] '%#'", self.selectedSearchParameter, self.searchString]];
NSLog(#"Predicate string %#",self.aPredicateString);
self.aPredicate = [NSPredicate predicateWithFormat:self.aPredicateString];
If user enters either \ or ' the code crashes with error.
I do not understand what the mistake is? Either special characters are not allowed in NSPredicate or should I format the predicate in different way.
I wonder, why you use all this self.aPredicateString stringByAppendingString, but I think, your predicate should look like this:
self.aPredicate = [NSPredicate predicateWithFormat:#"%# contains[cd] %#", self.selectedSearchParameter, self.searchString]];
with no '' around the %#
I was trying to validate URL links using regex, but not all the links are being completely identified. Can you please help me out?
I want the links to follow the pattern:
http://www.abcdef.org/xyz/content.aspx?menu id=190&id=3214
Assuming you are looking for a regular expression to match urls with a specific pattern:
You can use something like this to match http://www.abcdef.org/xyz/content.aspx?menu id=190&id=3214:
http://.*?/[a-zA-z]+/content.aspx\?menu id=\d+?&id=\d+
Regex for url with port in Objective c
It works well if don't have port number.
-(BOOL) validateUrl: (NSString *) candidate {
NSString *urlRegEx = #"^(http|https|ftp)\://(([a-zA-Z0-9-.]+\.[a-zA-Z]{2,3})|([0-2]*\d*\d\.[0-2]*\d*\d\.[0-2]*\d*\d\.[0-2]*\d*\d))(:[a-zA-Z0-9]*)?/?([a-zA-Z0-9-._\?\,\'/\+&%\$#\=~])*[^.\,)(\s]$";
NSPredicate *urlTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", urlRegEx];
return [urlTest evaluateWithObject:candidate];
}