[iOS]拾遗补阙

Posted 2020-08-17 幻想乡的技术宅

一、AFNetworking POST纯字符串

修改位置AFURLRequestSerialization

修改前

NSString * AFQueryStringFromParameters(NSDictionary *parameters) {
    NSMutableArray *mutablePairs = [NSMutableArray array];
    for (AFQueryStringPair *pair in AFQueryStringPairsFromDictionary(parameters)) {
        [mutablePairs addObject:[pair URLEncodedStringValue]];
    }

    return [mutablePairs componentsJoinedByString:@"&"];
}

修改后

NSString * AFQueryStringFromParameters(NSDictionary *parameters) {
    if ([parameters isKindOfClass:[NSString class]])
        return (NSString *)parameters;
    
    NSMutableArray *mutablePairs = [NSMutableArray array];
    for (AFQueryStringPair *pair in AFQueryStringPairsFromDictionary(parameters)) {
        [mutablePairs addObject:[pair URLEncodedStringValue]];
    }

    return [mutablePairs componentsJoinedByString:@"&"];
}

二、查找一个字符串中的多个相同子字符串

NSString *str = @"14 28 62 24 3 46 99 73 10 51 0 95 34 58 50 33 56 23 97 82 83 8 94 1 17 7 19 96 9 54";
NSString *searchString = @"1";

NSRange searchRange = NSMakeRange(0, [str length]);
NSRange range;

while ((range = [str rangeOfString:searchString options:0 range:searchRange]).location != NSNotFound)
{
    NSLog(@"%@",NSStringFromRange(range));
    
    searchRange = NSMakeRange(NSMaxRange(range), [str length] - NSMaxRange(range));
}

三、UITextField限制字数

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    NSInteger existedLength = textField.text.length;
    NSInteger selectedLength = range.length;
    NSInteger replaceLength = string.length;
    
    if (existedLength - selectedLength + replaceLength > 4)
        return NO;
    
    return YES;
}

 四、枚举数组元素

[array enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
    
}];

 五、为UILabel添加图片

NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = [UIImage imageNamed:@"image"];
attachment.bounds = CGRectMake(0, 0, 15, 15);

NSMutableAttributedString *string = [[NSMutableAttributedString alloc] init];
[string appendAttributedString:[NSAttributedString attributedStringWithAttachment:attachment]];
[string appendAttributedString:[[NSAttributedString alloc] initWithString:@"string"]];

UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(100, 100, 100, 30)];
label.attributedText = string;
[self.view addSubview:label];

 六、自适应屏幕大小

view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

 七、判断推送是否打开

BOOL registered = [[UIApplication sharedApplication] isRegisteredForRemoteNotifications];

 八、UIView转UIImage

- (UIImage *)viewToImage:(UIView *)view
{
    UIImage *image = [[UIImage alloc] init];
    UIGraphicsBeginImageContextWithOptions(view.frame.size, YES, [UIScreen mainScreen].scale);// 区域 透明 屏幕密度
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];
    image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return image;
}