iPhone开发笔记（三）

11、iPhone中变量值是否等于字符串的判断方法：

Objective-C代码

 [string1 isEqualToString:@ "123 " ];

12、iPhone的Framework的目录：
Mac---Developer---Platforms---iPhoneOS.platform---Developer---SDKs---iPhoneOS3.1.3.sdk---System---Library---Frameworks

  13、在iPhone中设置googlemap的经纬度：

Objective-C代码

 CLLocationCoordinate2D centerCoordinate;
 centerCoordinate.latitude = 39.9097;
 centerCoordinate.longitude = 105.3476;
 MKCoordinateSpan span;
 span.latitudeDelta = 30;
 span.longitudeDelta = 30;
 MKCoordinateRegion region;
 region.center = centerCoordinate;
 region.span = span;
 [mapview setRegion:region animated:TRUE];

14、翻页过渡效果：

Objective-C代码

 - (IBAction)backToMenus:(id)sender {
     CATransition *transition = [CATransition animation];
     transition.duration = 0.5;
     transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseIn];
     transition.type = kCATransitionFade;
     transition.delegate = self;
     [self.view.superview.layer addAnimation:transition forKey:nil];
     [self.view removeFromSuperview];
 }

15、fathercontroller的写法：

Objective-C代码

 在.h中：
 #import "DataBaseVC.h"
 @class  DataBaseVC;
 DataBaseVC *databasevc;
 在.m中：
 databasevc = [[DataBaseVC alloc] init];

16、将NSData类型的数据转换成NSString：

Objective-C代码

 NSString *theXML = [[NSString alloc] initWithBytes: [webData mutableBytes] length:[webData length] encoding:NSUTF8StringEncoding];  //webData为NSData类型

17、将NSString类型的数据转换成NSData：

Objective-C代码

 NSData *webData = [NSMutableData dataWithBytes:[theXML UTF8String] length:[theXML length]];;  //theXML为NSString类型

18、将特殊字符转义：

Objective-C代码

 NSString *str2 = [str1 stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

19、WiFi提示：

Objective-C代码

 在p-list中添加如下内容：
 Application uses Wi-Fi   YES
 SBUsesNetwork  3

20、iPhone获取系统时间：

Objective-C代码

 NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
 [formatter setDateFormat:@"YYYYMMddhhmmss" ];
 NSString *locationString=[formatter stringFromDate: [NSDate date]];