NSURL returns Nil Value

问题

Here Below is my code

NSString *string    = [NSString stringWithFormat:@" http://abc.com  /Demo/View.php?drinkId=%@&name=%@&comment=%@&date=%@&rating=%@&    ReqestType=SubmitComment",DrinkId,Name,Comment,Date,Rating];

NSURL *url          = [[NSURL alloc] initWithString:string];

Here in string there is value but url returns nil. Can Anyone tell why this happened.

Thanks ....

"This won't work, so here's what I did instead"

NSString *string    = [NSString stringWithFormat:@"http://abc.com/Demo/View.php?drinkId=%@&name=%@&comment=%@&date=%@&rating=%@&ReqestType=SubmitComment",DrinkId,Name,Comment,Date,Rating];

NSURL *url          = [[NSURL alloc] initWithString:string];

回答1:

NSURL will return nil for URLs that contain illegal chars, like spaces.

Before using your string with [NSURL URLWithString:] make sure to escape all the disallowed chars by using [NSString stringByAddingPercentEscapesUsingEncoding:].

Here is the class reference for NSString.

回答2:

Hi All Now My Problem Is solved here I did a mistake left a blank space before "http".

The correct code is

NSString *string    = [NSString stringWithFormat:@"http://myserver.com/Demo/View.php?drinkId=%@&name=%@&comment=%@&date=%@&rating=%@&ReqestType=SubmitComment",DrinkId,Name,Comment,Date,Rating];

NSURL *url          = [[NSURL alloc] initWithString:string];

来源：https://stackoverflow.com/questions/7258940/nsurl-returns-nil-value