字符串重组

 //1.多个数据拼接成一个字符串
        int year = 1988;
        int month = 4;
        int day = 15;
        NSString * date = [NSString stringWithFormat:@"%d年%d月%d日",year,month,day];
        NSLog(@"date %@",date);
        NSString * address = @"昌平区,金燕龙";
        NSString * dateAndAddrss = [NSString stringWithFormat:@"%@地址:%@",date,address];
        NSLog(@"dateAndAddress %@",dateAndAddrss);
        
        //2.字符串的末尾追加新的字符
        NSString * str1 = @"www.";
        NSString * str2 = [str1 stringByAppendingString:@"itcast.cn"];
        NSLog(@"str2 %@ str1 %@",str2,str1);
        
        //3.在制定的范围追加字符串
        NSString * str3 = @"www.cn";
        NSRange range = {4,0};
        // 4 location代表的时从哪个索引开始插入,length 代表的意思可以覆盖几个字符
        NSString * str4 = [str3 stringByReplacingCharactersInRange:range withString:@"itcast."];
        NSLog(@"str4 %@",str4);
        
        //4.使用新的字符,替换原有的字符
        NSString * str5 = @"www.itcast.cn";
        NSString * str6 = [str5 stringByReplacingOccurrencesOfString:@"w" withString:@"a"];
        NSLog(@"str6 %@",str6);
        
        //5.在字符串中删除特定的某些字符 胡汉三 hhs
        NSString * str7 = @"www---.itcatst.--cn";
        NSString * str8 = [str7 stringByReplacingOccurrencesOfString:@"-" withString:@""];
        NSLog(@"str8 %@",str8);
        
        //6.去掉字符串中的空格
        NSString * str9 = @"www  .itcat  .cn";
        NSString * str10 = [str9 stringByReplacingOccurrencesOfString:@" " withString:@""];
        NSLog(@"str10 %@",str10);