IOS学习笔记十六(NSString和NSMutableString)

1、NSString和NSMutableString

NSString是不变字符串类，有点像java里面的String,NSMutableString是可变字符串类，有点类似java里面的StringBuffer


2、测试demo

    int main(int argc, char * argv[]) {
        @autoreleasepool {
            unichar data[6] = {97, 98, 100, 101, 102, 103};
            NSString *str = [[NSString alloc] initWithCharacters:data length:6];
            NSLog(@"str is %@", str);
            char *cstr = "chenyu";
            NSString *str2 = [NSString stringWithUTF8String:cstr];
            NSLog(@"str2 is %@", str2);
     
            NSString *str3 = @"chenyu";
            NSString *name = @"陈喻";
            str3 = [str3 stringByAppendingString:@"chenyu"];
            NSLog(@"str3 is %@", str3);
            const char *cstr1 = [str3 UTF8String];
            NSLog(@"cstr1 is %s", cstr1);
            str3 = [str3 stringByAppendingFormat:@"hello %@ hello", name];
            NSLog(@"str3 is %@", str3);
            NSLog(@"str3 length is %lu", [str3 length]);
            NSString *s1 = [str3 substringToIndex:10];
            NSLog(@"s1 is %@", s1);
            NSString *s2 = [str3 substringFromIndex:5];
            NSLog(@"s2 is %@", s2);
            NSString *s3 = [str3 substringWithRange:NSMakeRange(5,10)];
            NSLog(@"s3 is %@", s3);
            NSRange pos = [str3 rangeOfString:@"陈喻"];
            NSLog(@"陈喻在str3中开始的位置：%ld,长度为%ld", pos.location, pos.length);
            str3 = [str3 uppercaseString];
            NSLog(@"str3 is %@", str3);
            NSMutableString *tstr = [NSMutableString stringWithString:@"hello"];
            [tstr appendString:@"chenyu"];
            NSLog(@"tstr is %@", tstr);
            [tstr appendFormat:@"hello word %@", @"chengongyu"];
            NSLog(@"tstr is %@", tstr);
            [tstr insertString:@"hello" atIndex:6];
            NSLog(@"tstr is %@", tstr);
            [tstr deleteCharactersInRange:NSMakeRange(6, 9)];
            NSLog(@"tstr is %@", tstr);
            [tstr replaceCharactersInRange:NSMakeRange(3, 6) withString:@"objectobject"];
            NSLog(@"tstr is %@", tstr);
        }
    }

 
 
 
3、运行结果

    str is abdefg
    str2 is chenyu
    str3 is chenyuchenyu
    cstr1 is chenyuchenyu
    str3 is chenyuchenyuhello 陈喻 hello
    str3 length is 26
    s1 is chenyuchen
    s2 is uchenyuhello 陈喻 hello
    s3 is uchenyuhel
    陈喻在str3中开始的位置：18,长度为2
    str3 is CHENYUCHENYUHELLO 陈喻 HELLO
    tstr is hellochenyu
    tstr is hellochenyuhello word chengongyu
    tstr is hellochellohenyuhello word chengongyu
    tstr is hellocuhello word chengongyu
    tstr is helobjectobjectllo word chengongyu

 

 

 
作者：chen.yu
深信服三年半工作经验，目前就职游戏厂商，希望能和大家交流和学习,
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