How do I know if my Nsurl is valid?
NSURL’s URLWithString returns nil if the URL passed is not valid. So, you can just check the return value to determine if the URL is valid. Just using URLWithString: will usually not be enough, you probably also want to check if the url has a scheme and a host, otherwise, urls such as al:/dsfhkgdsk will pass the test.
How can I check if a URL is valid in Swift?
Usage: if canOpenURL(“abc”) { print(“valid url.”) } else { print(“invalid url.”) }
How do I append to NSString?
The format specifier “%@” is used to insert string values. The example below uses a combination of whitespace and %@ format specifiers to append two strings to string1: NSString * string3 = [string1 stringByAppendingFormat:@” %@ %@”, string2, @”A third string.
Is valid in URL?
For example, you don’t need to encode the character ‘0’ to %30 as shown in the following table. It can be transmitted as is. But the encoding is still valid as per the RFC….The following table uses rules defined in RFC 3986 for URL encoding.
| Decimal | Character | URL Encoding (UTF-8) |
|---|---|---|
| 96 | ` | %60 |
| 97 | a | %61 |
| 98 | b | %62 |
| 99 | c | %63 |
How do you create a valid URL?
A URL is a valid URL if at least one of the following conditions holds:
- The URL is a valid URI reference [RFC3986].
- The URL is a valid IRI reference and it has no query component.
- The URL is a valid IRI reference and its query component contains no unescaped non-ASCII characters.
What is Nsbundle in iOS?
A representation of the code and resources stored in a bundle directory on disk.
What is Nsurl?
An object representing the location of a resource that bridges to URL ; use NSURL when you need reference semantics or other Foundation-specific behavior.
How do I append multiple strings in Objective C?
iPhone Development 101: Concatenating and Appending Strings. To concatenate two strings into a new string: NSString *string1 = @”This is”; NSString *string2 = @” a test. “; NSString *string3 = [string1 stringByAppendingString:string2]; // string3 is now @”This is a test.” string1 and string2 are unchanged.
How do you concatenate strings in Swift?
In the apple documentation for swift it states that you concatenate 2 strings by using the additions operator e.g. :
- let string1 = “hello”
- let string2 = ” there”
- var welcome = string1 + string2 4 // welcome now equals “hello there”
What is a valid URL?
A URL is a string used to identify a resource. A URL is a valid URL if at least one of the following conditions holds: The URL is a valid URI reference [RFC3986]. The URL is a valid IRI reference and its query component contains no unescaped non-ASCII characters. [RFC3987]