iOS开发中常用的方法（二）（持续更新）
2016-09-22 本文已影响675人
even_cheng
接上一篇 iOS开发中常用的方法(一)#
NSString常见用法:###
全部字符转为大写字母
-(NSString*)uppercaseString
全部字符转为小写字母
-(NSString*)lowercaseString
把每个单词首字母大写,其他字母小写:
-(NSString*)capitalizedString
比较两个对象的内容是否相同:
-(BOOL)isEqualToString:(NSString*)aString
比较两个字符串内容(ASCII码)的大小:
-(NSComparisonResult)compare:(NSString*)string;
比较两个字符串的地址是否相同用"=="
忽略大小写进行比较:
-(NSComparisonResult)caseInsensitiveCompare:(NSString*)string;
有条件比较:
- (NSComparisonResult)compare:(NSString *)string options (NSStringCompareOptions)mask;
options常用的三个条件:
NSCaseInsensitiveSearch:忽略大小写
NSLiteralSearch:默认的,全比较
NSNumericSearch:字母还是比较ascii码,如果遇到数字,比较数字的大小(还是一位一位的比较)
NSComparisonResult:枚举
三个值:NSOrderedAscending(升序), NSOrderedSame, NSOrderedDescending(降序)
判断是否sString开头:
-(BOOL)hasPrefix:(NSString*)sString;
判断是否sString结尾
-(BOOL)hasSuffix:(NSString*)sString;
检查字符串中是否包含sString:
-(NSRang)rangOfString:(NSString*)aString;
反方向搜索:
[str rangeOfString:@"str"options:NSBackwardsSearch];
从指定位置from开始截取到尾部:
-(NSString*)substringFormIndex:(NSUInteger)from;
从字符串的开头一直截取到指定位置to,但不包括该位置的字符:
-(NSString*)substringToIndex:(NSUInteger)to;
按照所给出的NSRange从字符串中截取字符串:
-(NSString*)substringWithRange:(NSRange)range;
用replacement替换target:
-(NSString*)stringByReplacingOccurrencesOfString:(NSSting*)target withString:(NSString*)replacement;
返回字符串长度:
-(NSUInteger)length;
返回index位置对应的字符:
-(unichar)characterAtIndex:(NSUInteger)index;
各种去掉:
- (NSString *)stringByTrimmingCharactersInSet:(NSCharacterSet *)set;
去掉头尾空格
+ (id)whitespaceCharacterSet;
去除所有的空格:
[str stringByRep]acingOccurrencesOfString:@" "withString:@“”]
去掉头尾所有的小写字母
+ (id)lowercaseLetterCharacterSet;
去掉头尾所有的大写字母
+ (id)uppercaseLetterCharacterSet;
去掉头尾的指定字符串
+ (id)characterSetWithCharactersInString:(NSString *)aString;
常见文件操作###
这个文件或文件夹(目录)是否存在
- (BOOL)fileExistsAtPath:(NSString *)path;
这个文件或文件夹是否存在, isDirectory代表是否为文件夹
- (BOOL)fileExistsAtPath:(NSString *)path isDirectory:(BOOL *)isDirectory;
这个文件或文件夹是否可读
- (BOOL)isReadableFileAtPath:(NSString *)path;
这个文件或文件夹是否可写
- (BOOL)isWritableFileAtPath:(NSString *)path;
这个文件或文件夹是否可删除
- (BOOL)isDeletableFileAtPath:(NSString *)path;
获得这个文件\文件夹的属性
- (NSDictionary *)attributesOfItemAtPath:(NSString *)path error:(NSError **)error;
查找给定路径下的所有子路径,返回一个数组,深度查找,不限于当前层,也会查找package的内容。
- (NSArray *)subpathsAtPath:(NSString *)path;
获的的当前子路径下的所有直接子内容必须是一个目录
- (NSArray *)contentsOfDirectoryAtPath:(NSString *)path error:(NSError **)error;
创建文件
- (BOOL)createFileAtPath:(NSString *)path contents:(NSData *)data attributes:(NSDictionary *)attire;
参数1:路径
参数2:文件内容
参数3:属性
创建文件夹(createIntermediates为YES代表自动创建中间的文件夹)
- (BOOL)createDirectoryAtPath:(NSString *)path withIntermediateDirectories:(BOOL) createIntermediates attributes:(NSDictionary *)attributes error:(NSError **)error;
拷贝,如果目标目录已经存在同名文件,则无法拷贝
- (BOOL)copyItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error;
移动(剪切)移动文件
- (BOOL)moveItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error;
删除文件
- (BOOL)removeItemAtPath:(NSString *)path error:(NSError **)error;
异常捕捉:
(try catch并不能检测所有的错误)
例: b = NO;
@try
//只能写一个
{
int rezult = a/b;
//这里放的是有可能出错的代码
}
@catch(NES xception *exception)
//可以写多个
{
//此处放出错以后我们处理的代码
}
@finally
//只能写一个
{
printf("abcd\n");
//不管是否出错这行代码一定会执行
}
获取类的所有属性
+ (NSDictionary *)getPropertys
{
NSMutableArray *proNames = [NSMutableArray array];
NSMutableArray *proTypes = [NSMutableArray array];
NSArray *theTransients = [[self class] transients];
unsigned int outCount, i;
objc_property_t *properties = class_copyPropertyList([self class], &outCount);
for (i = 0; i < outCount; i++) {
objc_property_t property = properties[i];
//获取属性名
NSString *propertyName = [NSString stringWithCString:property_getName(property) encoding:NSUTF8StringEncoding];
if ([theTransients containsObject:propertyName]) {
continue;
}
[proNames addObject:propertyName];
//获取属性类型等参数
NSString *propertyType = [NSString stringWithCString: property_getAttributes(property) encoding:NSUTF8StringEncoding];
if ([propertyType hasPrefix:@"T@"]) {
[proTypes addObject:SQLTEXT];
} else if ([propertyType hasPrefix:@"Ti"]||[propertyType hasPrefix:@"TI"]||[propertyType hasPrefix:@"Ts"]||[propertyType hasPrefix:@"TS"]||[propertyType hasPrefix:@"TB"]||[propertyType hasPrefix:@"Tq"]||[propertyType hasPrefix:@"TQ"]) {
[proTypes addObject:SQLINTEGER];
} else {
[proTypes addObject:SQLREAL];
}
}
free(properties);
return [NSDictionary dictionaryWithObjectsAndKeys:proNames,@"name",proTypes,@"type",nil];
}
获取沙盒路径
获取libraryCache路径
-(instancetype)appendCache
{
return [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:self.lastPathComponent];
}
获取Documents路径
-(instancetype)appendDocuments
{
return [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:self.lastPathComponent];
}
获取Temp路径
-(instancetype)appendTemp
{
return [NSTemporaryDirectory() stringByAppendingPathComponent:self.lastPathComponent];
}
XML解析
- 开始文档,只需要做一次,一般在这里初始化一个数组
- (void)parserDidStartDocument:(NSXMLParser *)parser{
}
- 开始节点,会调用多次
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(nullable NSString *)namespaceURI qualifiedName:(nullable NSString *)qName attributes:(NSDictionary<NSString *, NSString *> *)attributeDict{}
- 找到内容,会调用多次
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{
}
- 结束节点,会调用多次
- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(nullable NSString *)namespaceURI qualifiedName:(nullable NSString *)qName{}
- 结束节点,只会调用一次,拿到最终的结果
- (void)parserDidEndDocument:(NSXMLParser *)parser{}
XML解析第三方框架: GDataXMLElement
判断请求地址是否可用
+(BOOL) pingUrl: (NSString *) urlStr {
NSURL* URL = [NSURL URLWithString:urlStr];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
[request setHTTPMethod:@"HEAD"];
NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
__block BOOL result;
NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (error) {
result = NO;
}else{
result = YES;
}
}];
[task resume];
return result;
}
全局常量及宏定义
设置RGB颜色
#define RGB(r,g,b,a) [UIColor colorWithRed:r/255.0 green:g/255.0 blue:b/255.0 alpha:a]
弹框
#define HUD(text) if (((NSString *)text).length > 0) {MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:[UIApplication sharedApplication].keyWindow animated:YES];hud.mode = MBProgressHUDModeText;hud.labelText = text;[hud setRemoveFromSuperViewOnHide:YES];[hud hide:YES afterDelay:1];}
导航栏标题
#define SET_NAV_TITLE(_TITLE) ({UILabel *titleLabel = [[UILabel alloc] init];titleLabel.backgroundColor = [UIColor clearColor];titleLabel.textColor = [UIColor whiteColor];titleLabel.text = _TITLE;titleLabel.font=[UIFont boldSystemFontOfSize:18];[titleLabel sizeToFit];self.navigationItem.titleView = titleLabel;})
导航栏返回按钮
#define SET_BACK_ITEM(_IMAGENAME) ({UIButton *leftButton = [UIButton buttonWithType:UIButtonTypeCustom];[leftButton setFrame:CGRectMake(0, 0, 25, 25)];[leftButton setImage:[UIImage imageNamed:_IMAGENAME] forState:UIControlStateNormal];[leftButton addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchDown]; leftButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:leftButton];})
导航栏左右item
#define SET_NAV_ITEM(_TITLE,ISLEFT) ({UIButton *navButton = [UIButton buttonWithType:UIButtonTypeCustom];[navButton setFrame:CGRectMake(0, 0, 56, 56)];[navButton setTitle:_TITLE forState:UIControlStateNormal];[navButton addTarget:self action:@selector(navButtonClick:) forControlEvents:UIControlEventTouchDown];navButton.titleLabel.font = [UIFont systemFontOfSize:14];if(ISLEFT){navButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:navButton];} else {navButton.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:navButton];} })
判断是否是iOS8以上
#define iOS8Later ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
重定义NSLog
#define Log(format, ...) NSLog(@"%s--line:%d " format, __FUNCTION__, __LINE__, ##__VA_ARGS__)
UserDefaults
#define kUserDefaults [NSUserDefaults standardUserDefaults]
```
切换跟控制器的通知
```
#define kSwitchRootViewControllerNotification @"SwitchRootViewControllerNotification"
```
Navigaiton高度
```
#define NavBarHeight 64
```
屏幕高度
```
#define kScreenHeight [UIScreen mainScreen].bounds.size.height
```
得到屏幕宽度
```
#define kScreenWidth [UIScreen mainScreen].bounds.size.width
```
屏幕适配
```
#define kWidthValue(value) ((value)/375.0f*[UIScreen mainScreen].bounds.size.width)
#define kHeightValue(value) ((value)/667.0f*[UIScreen mainScreen].bounds.size.height)
```
判断是真机还是模拟器
```
#if TARGET_OS_IPHONE
//iPhone Device
#endif
#if TARGET_IPHONE_SIMULATOR
//iPhone Simulator
#endif
```
打印日志
```
#ifdef DEBUG
#define LRLog(...) NSLog(@"%s 第%d行 \n %@\n\n",__func__,__LINE__,[NSString stringWithFormat:__VA_ARGS__])
#else
#define LRLog(...)
#endif
```
强弱引用
```
#define kWeakSelf(type) __weak typeof(type) weak##type = type;
#define kStrongSelf(type) __strong typeof(type) type = weak##type;
```
设置控件圆角边框
```
#define kBorderRadius(Obj, Radius, Width, Color)\
[Obj.layer setCornerRadius:(Radius)];\
[Obj.layer setMasksToBounds:YES];\
[Obj.layer setBorderWidth:(Width)];\
[Obj.layer setBorderColor:[Color CGColor]]
```
GCD
```
//GCD - 一次性执行
#define kDISPATCH_ONCE_BLOCK(onceBlock) static dispatch_once_t onceToken; dispatch_once(&onceToken, onceBlock);
//GCD - 在Main线程上运行
#define kDISPATCH_MAIN_THREAD(mainQueueBlock) dispatch_async(dispatch_get_main_queue(), mainQueueBlock);
//GCD - 开启异步线程
#define kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), globalQueueBlocl);
```
获取沙盒目录
```
//获取temp
#define kPathTemp NSTemporaryDirectory()
//获取沙盒 Document
#define kPathDocument [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]
//获取沙盒 Cache
#define kPathCache [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject]
```
###获取成员变量
```
//定义一个保存成员变量个数的变量
unsignedint count = 0;
Ivar* ivars = class_copyIvarList([obj class], &count);
//遍历成员列表找到需要的属性
for (int i = 0; i < count; i++)
{
//获取成员
Ivar ivar = ivars[i];
//获取属性名
constchar* name = ivar_getName(ivar);
//属性的类型
constchar * type = ivar_getTypeEncoding(ivar);
//转化成字符串
NSString* nameStr = [NSStringstringWithUTF8String:name];
NSString* typeStr = [NSStringstringWithUTF8String:type]; NSLog(@"name:%@,type:%@",nameStr,typeStr);
//给成员变量赋值
if ([nameStr isEqualToString:@"_internalView"])
{
[obj setValue:imageView forKey:@"_internalView"];
}
}
```
###修改textField的placeholder的字体颜色、大小
```
self.textField.placeholder = @"请输入用户名";
[self.textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[self.textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];
```
###计算两点距离
```
static __inline__ CGFloat CGPointDistanceBetweenTwoPoints(CGPoint point1, CGPoint point2) { CGFloat dx = point2.x - point1.x; CGFloat dy = point2.y - point1.y; return sqrt(dx*dx + dy*dy);}
```
###收起键盘的相关方法
```
1、点击键盘的Return收起键盘
- (BOOL)textFieldShouldReturn:(UITextField *)textField { return [textField resignFirstResponder]; }
2、点击View收起键盘
[self.view endEditing:YES];
3、统一收起键盘
[[[UIApplication sharedApplication] keyWindow] endEditing:YES];
```
###获取当前硬盘空间
```
NSFileManager *fm = [NSFileManager defaultManager];
NSDictionary *fattributes = [fm attributesOfFileSystemForPath:NSHomeDirectory() error:nil];
NSLog(@"容量%lldG",[[fattributes objectForKey:NSFileSystemSize] longLongValue]/1000000000);
NSLog(@"可用%lldG",[[fattributes objectForKey:NSFileSystemFreeSize] longLongValue]/1000000000);
```
###将UIColor转为UIImage
```
- (UIImage *)createImageWithColor:(UIColor *)color
{
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *theImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return theImage;
}
```
###SDWebImage清理缓存
```
// 清理内存
[[SDImageCache sharedImageCache] clearMemory];
// 清理webview 缓存
NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (NSHTTPCookie *cookie in [storage cookies]) {
[storage deleteCookie:cookie];
}
NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
[config.URLCache removeAllCachedResponses];
[[NSURLCache sharedURLCache] removeAllCachedResponses];
// 清理硬盘
[[SDImageCache sharedImageCache] clearDiskOnCompletion:^{
[MBProgressHUD hideAllHUDsForView:self.view animated:YES];
[self.tableView reloadData];
}];
```
