关于ios:iOS之字符串处理截取字符串匹配字符串分隔字符串大小写转换

1. 截取字符串

NSString *string =@"123456d890";
NSString *str1 = [string substringToIndex:5];// 截取掉下标 5 之前的字符串
NSLog(@"截取的值为：%@",str1);
 NSString *str2 = [string substringFromIndex:3];// 截取掉下标 3 之后的字符串
NSLog(@"截取的值为：%@",str2);

2. 匹配字符串

NSString *string =@"sd 是 sfsfsAdfsdf";
NSRange range = [string rangeOfString:@"Ad"];// 匹配失去的下标
NSLog(@"rang:%@",NSStringFromRange(range));
string = [string substringWithRange:range];// 截取范畴内的字符串
NSLog(@"截取的值为：%@",string);

3. 分隔字符串

NSString *string =@"sdfsfsfsAdfsdf";
    
NSArray *array = [string componentsSeparatedByString:@"A"]; // 从字符 A 中分隔成 2 个元素的数组
NSLog(@"array:%@",array); // 后果是 adfsfsfs 和 dfsdf

// 用一段字符串 替换一段字符串
NSString *strUrl = [urlString stringByReplacingOccurrencesOfString:@“;"withString:@""];
// 替换某段字符
NSString *idCard = [Str stringByReplacingCharactersInRange:NSMakeRange(5, 6) withString:@"*****************"];
NSLog(@"idCard:%@",idCard); 

4. 字母大小写转换

NSString  *str =@"AAaaBB3bb";
// 把字符串全副转化为小写
NSString *str1 = [str lowercaseString];
NSString * str2 = str.lowercaseString;

// 把字符串全副转化为大写 (外面蕴含数字没事)
str1 = [str uppercaseString];
str2 = str.uppercaseString;

// 结尾大写，其余小写 (外面蕴含数字, 数字后的字母会大写)
str1 =[str capitalizedString];
str2 =str.capitalizedString;

DLog(@"%@ - %@",str1, str2);