• 判斷字符串是不是以中文開頭

- (BOOL)isChineseFirst:(NSString *)firstString {//是否以中文開頭(unicode中文編碼范圍是0x4e00~0x9fa5)int utfCode = 0;void *buffer = &utfCode;NSRange range = NSMakeRange(0, 1);//判斷是不是中文開頭的,buffer->獲取字符的字節數據 maxLength->buffer的最大長度 usedLength->實際寫入的長度，不需要的話可以傳遞NULL encoding->字符編碼常數，不同編碼方式轉換后的字節長是不一樣的，這里我用了UTF16 Little-Endian，maxLength為2字節，如果使用Unicode，則需要4字節 options->編碼轉換的選項，有兩個值，分別是NSStringEncodingConversionAllowLossy和NSStringEncodingConversionExternalRepresentation range->獲取的字符串中的字符范圍,這里設置的第一個字符 remainingRange->建議獲取的范圍，可以傳遞NULLBOOL isChinese = [firstString getBytes:buffer maxLength:2 usedLength:NULL encoding:NSUTF16LittleEndianStringEncoding options:NSStringEncodingConversionExternalRepresentation range:range remainingRange:NULL];if (isChinese && (utfCode >= 0x4e00 && utfCode <= 0x9fa5))return YES;elsereturn NO; }

• 鍵盤回收

- (void)setUpForDismissKeyboard {UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapAnywhereToDismissKeyboard:)];NSOperationQueue *operation = [NSOperationQueue mainQueue];[[NSNotificationCenter defaultCenter] addObserverForName:UIKeyboardWillShowNotification object:nil queue:operation usingBlock:^(NSNotification * _Nonnull note) {[self.view addGestureRecognizer:tapGesture];}];[[NSNotificationCenter defaultCenter] addObserverForName:UIKeyboardWillHideNotification object:nil queue:operation usingBlock:^(NSNotification * _Nonnull note) {[self.view removeGestureRecognizer:tapGesture];}]; }

• 禁止側滑返回上一個界面

if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.enabled = NO;}

• 隱藏導航欄最下面的黑線

- (void)hiddenNavLine {if ([self.navigationController.navigationBar respondsToSelector:@selector( setBackgroundImage:forBarMetrics:)]){NSArray *list=self.navigationController.navigationBar.subviews;for (id obj in list) {if ([UIDevice currentDevice].systemVersion.floatValue >= 10.0) {UIView *view = (UIView*)obj;for (id obj2 in view.subviews) {if ([obj2 isKindOfClass:[UIImageView class]]) {UIImageView *image = (UIImageView*)obj2;image.hidden = YES;}}}}} }

• 去除自帶的searchBar的背景View

- (void)removeSearchBarBackGroundView {for(int i = 0 ;i < _searchBar.subviews.count;i++){UIView * backView = _searchBar.subviews[i];if ([backView isKindOfClass:NSClassFromString(@"UISearchBarBackground")] == YES) {[backView removeFromSuperview];[_searchBar setBackgroundColor:[UIColor clearColor]];break;} else {NSArray * arr = _searchBar.subviews[i].subviews;for(int j = 0;j < arr.count; j++){UIView * barView = arr[i];if ([barView isKindOfClass:NSClassFromString(@"UISearchBarBackground")] == YES) {[barView removeFromSuperview];[_searchBar setBackgroundColor:[UIColor clearColor]];break;}}}} }

• 標簽欄的背景圖顯示錯亂問題解決辦法：

//將圖片如下設置 [[UIImage imageNamed:@"me@2x.png"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]

• 網絡請求設置超時請求（基于AFNetworking3.0封裝的GET，POST請求用方法）

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager]; [manager.requestSerializer willChangeValueForKey:@"timeoutInterval"];manager.requestSerializer.timeoutInterval = 15.f;[manager.requestSerializer didChangeValueForKey:@"timeoutInterval"];

• 實用的獲取圖片的方法，防止內存溢出：

// 建議使用該方法： NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"圖片" ofType:@"png"]; UIImage *image = [[UIImage alloc] initWithContentsOfFile:imagePath];// 不建議使用該方法： UIImage *image = [UIImage imageNamed:@"圖片.png"];

總結

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