請考慮下面的代碼:如何避免在目標C NULL值
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
NSURL *url = [NSURL URLWithString:@"http://localhost/faq.php?faqType=2"]; // Modify this to
NSString *jsonreturn = [[NSString alloc] initWithContentsOfURL:url]; // Pulls the URL
NSLog(@"jsonreturn=%@",jsonreturn); // Look at the console and you can see what the restults are
NSData *jsonData = [jsonreturn dataUsingEncoding:NSUTF32BigEndianStringEncoding];
NSError *error = nil;
// In "real" code you should surround this with try and catch
NSDictionary *dict = [[CJSONDeserializer deserializer] deserializeAsDictionary:jsonData error:&error];
if (dict)
{
rows = [[dict objectForKey:@"faq"] retain];
}
[jsonreturn release];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
// Configure the cell.
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier] autorelease];
}
NSDictionary *dict1 = [rows objectAtIndex:indexPath.row];
NSLog(@"%@", dict1);
cell.textLabel.text = [dict1 objectForKey:@"faqQues"];
}
//if it is not getting NULL value then UItableView is ok
{"faq":[{"faqQues":"this is mr.mack?"},{"faqQues":"is he good man?"}]}
//but if the data is like NULL
{"faq":[{"faqQues":"this is mr.mack?"},{"faqQues":null}]} // then it is creating EXEC_BAD_ACCESS error,
所以如何避免NULL或檢查空值,或者如何解決這個問題?