%c一個單一的字符
%d一個十進制整數
%i一個整數
%e, %f, %g一個浮點數
%o一個八進制數
%s一個字符串
%x一個十六進制數
%p一個指針
%n一個等于讀取字符數量的整數
%u一個無符號整數
%[]一個字符集
%%一個精度符號
//一、NSString
/*----------------創建字符串的方法----------------*/
1、創建常量字符串。
NSString *astring = @"This is a String!";
2、創建空字符串,給予賦值。
NSString *astring = [[NSString alloc] init];
astring = @"This is a String!";
NSLog(@"astring:%@",astring);
[astring release];
3、在以上方法中,提升速度:initWithString方法
NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];
NSLog(@"astring:%@",astring);
[astring release];
4、用標準c創建字符串:initWithCString方法
char *Cstring = "This is a String!";
NSString *astring = [[NSString alloc] initWithCString:Cstring];
NSLog(@"astring:%@",astring);
[astring release];
5、創建格式化字符串:占位符(由一個%加一個字符組成)
int i = 1;
int j = 2;
NSString *astring = [[NSString alloc]
initWithString:[NSString stringWithFormat:@"%d.This is %i string!",i,j]];
NSLog(@"astring:%@",astring);
[astring release];
6、創建臨時字符串
NSString *astring;
astring = [NSString stringWithCString:"This is a temporary string"];
NSLog(@"astring:%@",astring);
/*----------------從文件讀取字符串:initWithContentsOfFile方法----------------*/
NSString *path = @"astring.text";
NSString *astring = [[NSString alloc] initWithContentsOfFile:path];
NSLog(@"astring:%@",astring);
[astring release];
/*----------------寫字符串到文件:writeToFile方法----------------*/
NSString *astring = [[NSString alloc] initWithString:@"This is a String!"];
NSLog(@"astring:%@",astring);
NSString *path = @"astring.text";
[astring writeToFile: path atomically: YES];
[astring release];
/*----------------比較兩個字符串----------------*/
用C比較:strcmp函數
char string1[] = "string!";
char string2[] = "string!";
if(strcmp(string1, string2) = = 0)
{
NSLog(@"1");
}
isEqualToString方法
NSString *astring01 = @"This is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 isEqualToString:astring02];
NSLog(@"result:%d",result);
compare方法(comparer返回的三種值)
NSString *astring01 = @"This is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 compare:astring02] = = NSOrderedSame;
NSLog(@"result:%d",result);
NSOrderedSame判斷兩者內容是否相同
NSString *astring01 = @"This is a String!";
NSString *astring02 = @"this is a String!";
BOOL result = [astring01 compare:astring02] = = NSOrderedAscending;
NSLog(@"result:%d",result);
//NSOrderedAscending判斷兩對象值的大小(按字母順序進行比較,astring02大于astring01為真)
NSString *astring01 = @"this is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 compare:astring02] = = NSOrderedDescending;
NSLog(@"result:%d",result);
//NSOrderedDescending判斷兩對象值的大小(按字母順序進行比較,astring02小于astring01為真)
不考慮大 小寫比較字符串1
NSString *astring01 = @"this is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 caseInsensitiveCompare:astring02] = = NSOrderedSame;
NSLog(@"result:%d",result);
//NSOrderedDescending判斷兩對象值的大小(按字母順序進行比較,astring02小于astring01為 真)
不考慮大小寫比較字符串2
NSString *astring01 = @"this is a String!";
NSString *astring02 = @"This is a String!";
BOOL result = [astring01 compare:astring02
options:NSCaseInsensitiveSearch | NSNumericSearch] = = NSOrderedSame;
NSLog(@"result:%d",result);
//NSCaseInsensitiveSearch:不區分大小寫比較NSLiteralSearch:進行完全比較,區分大小寫NSNumericSearch:比較字符串的字符個數,而不是字符值。
/*----------------改變字符串的大小寫----------------*/
NSString *string1 = @"A String";
NSString *string2 = @"String";
NSLog(@"string1:%@",[string1 uppercaseString]);//大寫
NSLog(@"string2:%@",[string2 lowercaseString]);//小寫
NSLog(@"string2:%@",[string2 capitalizedString]);//首字母大小
/*----------------在串中搜索子串----------------*/
NSString *string1 = @"This is a string";
NSString *string2 = @"string";
NSRange range = [string1 rangeOfString:string2];
int location = range.location;
int leight = range.length;
NSString *astring = [[NSString alloc]
initWithString:[NSString stringWithFormat:@"Location:%i,Leight:%i"
,location,leight]];
NSLog(@"astring:%@",astring);
[astring release];
/*----------------抽取子串----------------*/
-substringToIndex:從字符串的開頭一直截取到指定的位置,但不包括該位置的字符
NSString *string1 = @"This is a string";
NSString *string2 = [string1 substringToIndex:3];
NSLog(@"string2:%@",string2);
-substringFromIndex:以指定位置開始(包括指定位置的字符),并包括之后的全部字符
NSString *string1 = @"This is a string";
NSString *string2 = [string1 substringFromIndex:3];
NSLog(@"string2:%@",string2);
-substringWithRange: //按照所給出的位置,長度,任意地從字符串中截取子串
NSString *string1 = @"This is a string";
NSString *string2 = [string1 substringWithRange:NSMakeRange(0, 4)];
NSLog(@"string2:%@",string2);
const char *fieldValue = [valuecStringUsingEncoding:NSUTF8StringEncoding];
const char *fieldValue = [value UTF8String];
NSString轉NSData
NSString* str= @"kilonet";
NSData* data=[str dataUsingEncoding:NSUTF8StringEncoding];
Date format用法:
-(NSString *) getDay:(NSDate *) d
{
NSString *s ;
NSDateFormatter *format = [[NSDateFormatter alloc] init];
[format setDateFormat:@"YYYY/MM/dd hh:mm:ss"];
s = [format stringFromDate:d];
[format release];
return s;
}
各地時區獲取:
NSDate *nowDate = [NSDate new];
NSDateFormatter *formatter=[[NSDateFormatter alloc] init];
[formattersetDateFormat:@"yyyy/MM/dd HH:mm:ss"];
//根據時區名字獲取當前時間,如果該時區不存在,默認獲取系統當前時區的時間
//NSTimeZone* timeZone = [NSTimeZone timeZoneWithName:@"Europe/Andorra"];
//[formatter setTimeZone:timeZone];
//獲取所有的時區名字
NSArray *array = [NSTimeZone knownTimeZoneNames];
//NSLog(@"array:%@",array);
//for循環
//for(int i=0;i<[array count];i++)
//{
//NSTimeZone* timeZone = [NSTimeZone timeZoneWithName:[array objectAtIndex:i]];
//[formatter setTimeZone:timeZone];
//NSString *locationTime = [formatter stringFromDate:nowDate];
//NSLog(@"時區名字:%@:時區當前時間: %@",[array objectAtIndex:i],locationTime);
////NSLog(@"timezone name is:%@",[array objectAtIndex:i]);
//}
//快速枚舉法
for(NSString *timeZoneName in array){
[formatter setTimeZone:[NSTimeZone timeZoneWithName:timeZoneName]];
NSLog(@"%@,%@",timeZoneName,[formatter stringFromDate:nowDate]);
}
[formatter release];
[nowDate release];
NSCalendar用法:
-(NSString *) getWeek:(NSDate *) d {
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
unsigned units = NSYearCalendarUnit | NSMonthCalendarUnit |NSDayCalendarUnit | NSWeekdayCalendarUnit;
NSDateComponents *components = [calendar components:units fromDate:d];
[calendar release];
switch ([components weekday]) {
case 2:
return @"Monday";
break;
case 3:
return @"Tuesday";
break;
case 4:
return @"Wednesday";
break;
case 5:
return @"Thursday";
break;
case 6:
return@"Friday";
break;
case 7:
return@"Saturday";
break;
case 1:
return @"Sunday";
break;
default:
return @"No Week";
break;
}
//用components,我們可以讀取其他更多的數據。
}
4.用Get方式讀取網絡數據:
將網絡數讀取為字符串
- (NSString *) getDataByURL:(NSString *) url {
return [[NSString alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]] encoding:NSUTF8StringEncoding];
}
//讀取網絡圖片
- (UIImage *) getImageByURL:(NSString *) url {
return [[UIImage alloc] initWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[url stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]]];
}
多線程
[NSThread detachNewThreadSelector:@selector(scheduleTask) toTarget:self withObject:nil];
-(void) scheduleTask {
//create a pool
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
//release the pool;
[pool release];
}
//如果有參數,則這么使用:
[NSThread detachNewThreadSelector:@selector(scheduleTask:) toTarget:self withObject:[NSDate date]];
-(void) scheduleTask:(NSDate *) mdate {
//create a pool
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
//release the pool;
[pool release];
}
//注意selector里有冒號。
//在線程里運行主線程里的方法
[self performSelectorOnMainThread:@selector(moveToMain) withObject:nil waitUntilDone:FALSE];
6.定時器NSTimer用法:
代碼
//一個可以自動關閉的Alert窗口
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:[@"一個可以自動關閉的Alert窗口"
delegate:nil
cancelButtonTitle:nil //NSLocalizedString(@"OK", @"OK")//取消任何按鈕
otherButtonTitles:nil];
//[alert setBounds:CGRectMake
(alert.bounds.origin.x, alert.bounds.origin.y,
alert.bounds.size.width, alert.bounds.size.height+30.0)];
[alert show];
UIActivityIndicatorView *indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
// Adjust the indicator so it is up a few pixels from the bottom of the alert
indicator.center = CGPointMake(alert.bounds.size.width/2,alert.bounds.size.height-40.0);
[indicator startAnimating];
[alert insertSubview:indicator atIndex:0];
[indicator release];
[NSTimer scheduledTimerWithTimeInterval:3.0f
target:self
selector:@selector(dismissAlert:)
userInfo:[NSDictionary dictionaryWithObjectsAndKeys:alert,
@"alert", @"testing ", @"key" ,nil]//如果不用傳遞參數,那么可以將此項設置為nil.
repeats:NO];
NSLog(@"release alert");
[alert release];
-(void) dismissAlert:(NSTimer *)timer{
NSLog(@"release timer");
NSLog([[timer userInfo]objectForKey:@"key"]);
UIAlertView *alert = [[timer userInfo]objectForKey:@"alert"];
[alert dismissWithClickedButtonIndex:0 animated:YES];
}
定時器停止使用:
[timer invalidate];
timer = nil;
7.用戶缺省值NSUserDefaults讀取:
//得到用戶缺省值
NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
//在缺省值中找到AppleLanguages,返回值是一個數組
NSArray* languages = [defs objectForKey:@"AppleLanguages"];
NSLog(@"all language語言is %@", languages);
//在得到的數組中的第一個項就是用戶的首選語言了
NSLog(@"首選語言is %@",[languages objectAtIndex:0]);
//get the language & country code
NSLocale *currentLocale = [NSLocale currentLocale];
NSLog(@"Language Code is %@", [currentLocale objectForKey:NSLocaleLanguageCode]);
NSLog(@"Country Code is %@", [currentLocale objectForKey:NSLocaleCountryCode
8. View之間切換的動態效果設置:
SettingsController *settings = [[SettingsController alloc]initWithNibName:@"SettingsView" bundle:nil];
settings.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;//水平翻轉
[self presentModalViewController:settings animated:YES];
[settings release];
9.NSScrollView滑動用法:
-(void) scrollViewDidScroll:(UIScrollView *)scrollView{
NSLog(@"正在滑動中...");
}
//用戶直接滑動NSScrollView,可以看到滑動條
-(void) scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
}
//通過其他控件觸發NSScrollView滑動,看不到滑動條
- (void) scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView {
}
11.鍵盤處理系列
//set the UIKeyboard to switch to a different text field when you press return
//switch textField to the name of your textfield
[textField becomeFirstResponder];
srandom(time(NULL)); //隨機數種子
id d = random(); //隨機數
4. iPhone的系統目錄:
//得到Document目錄:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
//得到temp臨時目錄:
NSString *tempPath = NSTemporaryDirectory();
//得到目錄上的文件地址:
NSString *文件地址= [目錄地址stringByAppendingPathComponent:@"文件名.擴展名"];
5.狀態欄顯示Indicator:
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
6.app Icon顯示數字:
- (void)applicationDidEnterBackground:(UIApplication *)application{
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:5];
}
7.sqlite保存地址:
代碼
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *thePath = [paths objectAtIndex:0];
NSString *filePath = [thePath stringByAppendingPathComponent:@"kilonet1.sqlite"];
NSString *dbPath = [[[NSBundle mainBundle] resourcePath]
stringByAppendingPathComponent:@"kilonet2.sqlite"];
8.Application退出:exit(0);
9. AlertView,ActionSheet的cancelButton點擊事件:
代碼
-(void) actionSheet :(UIActionSheet *) actionSheet didDismissWithButtonIndex:(NSInteger) buttonIndex {
NSLog(@"cancel actionSheet........");
//當用戶按下cancel按鈕
if( buttonIndex == [actionSheet cancelButtonIndex]) {
exit(0);
}
////當用戶按下destructive按鈕
//if( buttonIndex == [actionSheet destructiveButtonIndex]) {
//// DoSomething here.
//}
}
- (void)alertView:(UIAlertView *)alertView willDismissWithButtonIndex:(NSInteger)buttonIndex {
NSLog(@"cancel alertView........");
if (buttonIndex == [alertView cancelButtonIndex]) {
exit(0);
}
}
10.給Window設置全局的背景圖片:
window.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"coolblack.png"]];
11. UITextField文本框顯示及對鍵盤的控制:
代碼
#pragma mark -
#pragma mark UITextFieldDelegate
//控制鍵盤跳轉
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
if (textField == _txtAccount) {
if ([_txtAccount.text length]==0) {
return NO;
}
[_txtPassword becomeFirstResponder];
} else if (textField == _txtPassword) {
[_txtPassword resignFirstResponder];
}
return YES;
}
//輸入框背景更換
-(BOOL) textFieldShouldBeginEditing:(UITextField *)textField{
[textField setBackground:[UIImage imageNamed:@"ctext_field_02.png"]];
return YES;
}
-(void) textFieldDidEndEditing:(UITextField *)textField{
[textField setBackground:[UIImage imageNamed:@"ctext_field_01.png"]];
}
12.UITextField文本框前面空白寬度設置以及后面組合按鈕設置:
代碼
//給文本輸入框后面加入空白
_txtAccount.rightView = _btnDropDown;
_txtAccount.rightViewMode =UITextFieldViewModeAlways;
//給文本輸入框前面加入空白
CGRect frame = [_txtAccount frame];
frame.size.width = 5;
UIView *leftview = [[UIView alloc] initWithFrame:frame];
_txtAccount.leftViewMode = UITextFieldViewModeAlways;
_txtAccount.leftView = leftview;
13. UIScrollView設置滑動不超出本身范圍:
[fcScrollView setBounces:NO];
14.在drawRect里畫文字:
UIFont * f = [UIFont systemFontOfSize:20];
[[UIColor darkGrayColor] set];
NSString * text = @"hi \nKiloNet";
[text drawAtPoint:CGPointMake(center.x,center.y) withFont:f];
15. NSArray查找是否存在對象時用indexOfObject,如果不存在則返回為NSNotFound.
16. NString與NSArray之間相互轉換:
array = [string componentsSeparatedByString:@","];
string = [[array valueForKey:@"description"] componentsJoinedByString:@","];
17. TabController隨意切換tab bar:
[self.tabBarController setSelectedIndex:tabIndex];
或者self.tabBarController.selectedIndex = tabIndex;
或者實現下面的delegate來撲捉tab bar的事件:
代碼-(BOOL) tabBarController:(UITabBarController *)tabBarController
shouldSelectViewController:(UIViewController *)viewController
{if ([viewController.tabBarItem.title isEqualToString: NSLocalizedString(@"Logout",nil)])
{[self showLogout];return NO;}return YES;}
18.自定義View之間切換動畫:
代碼
- (void) pushController: (UIViewController*) controller
withTransition: (UIViewAnimationTransition) transition
{
[UIView beginAnimations:nil context:NULL];
[self pushViewController:controller animated:NO];
[UIView setAnimationDuration:.5];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationTransition:transition forView:self.view cache:YES];
[UIView commitAnimations];
}
CATransition *transition = [CATransition animation];
transition.duration = kAnimationDuration;
transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionPush;
transition.subtype = kCATransitionFromTop;
transitioning = YES;
transition.delegate = self;
[self.navigationController.view.layer addAnimation:transition forKey:nil];
self.navigationController.navigationBarHidden = NO;
[self.navigationController pushViewController:tableViewController animated:YES];
20.計算字符串長度:
CGFloat w = [title sizeWithFont:[UIFont fontWithName:@"Arial" size:18]].width;
23.在使用UISearchBar時,將背景色設定為clearColor,或者將translucent設為YES,都不能使背景透明,經過一番研究,發現了一種超級簡單和實用的方法:
1
[[searchbar.subviews objectAtIndex:0]removeFromSuperview];
背景完全消除了,只剩下搜索框本身了。
24.圖像與緩存:
UIImageView *wallpaper = [[UIImageView alloc] initWithImage:
[UIImage imageNamed:@"icon.png"]]; //會緩存圖片
UIImageView *wallpaper = [[UIImageView alloc] initWithImage:
[UIImage imageWithContentsOfFile:@"icon.png"]]; //不會緩存圖片
25. iphone-常用的對視圖圖層(layer)的操作
對圖層的操作:
(1.給圖層添加背景圖片:
myView.layer.contents = (id)[UIImage imageNamed:@"view_BG.png"].CGImage;
(2.將圖層的邊框設置為圓腳
myWebView.layer.cornerRadius = 8;
myWebView.layer.masksToBounds = YES;
(3.給圖層添加一個有色邊框
myWebView.layer.borderWidth = 5;
myWebView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09 blue:0.07 alpha:1] CGColor];
將多個字符替換成空
NSCharacterSet *cs = [NSCharacterSet characterSetWithCharactersInString:@"1234567890|"];
NSString *resultstr = [[yourstr componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@" "];