Iphone development: email Verification

Determine whether a valid email address is used.

-(BOOL) is_email_can_be_open :( NSString *) email
{
If (0! = [Email rangeOfString: @ "@"]. length) & (0! = [Email rangeOfString: @ "."]. length ))
{
NSMutableCharacterSet * invalidCharSet = [[[NSCharacterSet alphanumericCharacterSet] invertedSet] mutableCopy] autorelease];
[InvalidCharSet removeCharactersInString: @ "_-"];

Nsange range1 = [email rangeOfString: @ "@" options: NSCaseInsensitiveSearch];

// If username part contains any character other ".""_""-"

NSString * usernamePart = [email substringToIndex: range1.location];
NSArray * stringsArray1 = [usernamePart componentsSeparatedByString: @ "."];
For (NSString * string in stringsArray1)
{
Nsange rangeofinav1_chars = [string rangeOfCharacterFromSet: invalidCharSet];
If (rangeofinav1_chars. length! = 0 | [string isEqualToString: @ ""])
{
Return NO;
}
}

NSString * domainPart = [email substringFromIndex: range1.location + 1];
NSArray * stringsArray2 = [domainPart componentsSeparatedByString: @ "."];

For (NSString * string in stringsArray2)
{
Nsange rangeofinav1_chars = [string rangeOfCharacterFromSet: invalidCharSet];
If (rangeofinav1_chars. length! = 0 | [string isEqualToString: @ ""])
{
Return NO;
}
}

Return YES;
}
Return NO;
}

 

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