NSString NSArray和可变字符串、数组的用法

//
使用实例方法创建NSString对象

NSString *string1
=
[[NSStringalloc]initWithFormat:@"姓名流年"];

NSLog(@"%@", string1);

NSString *string2
=
[[NSStringalloc]initWithFormat:@"Ming"];

NSLog(@"%@", string2);

NSString *string3
=
[[NSStringalloc]initWithFormat:@"姓名：%@ 
年龄：%d 
爱好：%@",
@"嘿嘿",
100,
@"吃、喝、玩"
];

NSLog(@"%@",string3);

//把字符串转为数值类型

NSInteger intstr =
[@"124" integerValue];

NSLog(@"%ld",intstr);

double m =
[@"1000.00432" doubleValue];

NSLog(@"%lf", m);

//大小写转换

NSString *m1 = @"Have a good
day";

NSString *m2 = [m1
uppercaseString];

NSString *m3 = [m1
lowercaseString];

NSString *m4 = [m1
capitalizedString];

NSLog(@"===%@  ++++%@ 
****%@", m2, m3, m4);

//可变字符串

NSMutableString *string1
= [[NSMutableString
alloc]initWithFormat:@"蓝欧科技有限公司"];

NSMutableString *string2
= [NSMutableString
stringWithFormat:@"蓝欧科技有限公司"];

//拼接字符串

[string1
appendString:@".txt"];

NSLog(@"%@", string1);

//插入字符串

[string2
insertString:@"3G" atIndex:2];

NSLog(@"%@", string1);

//删除字符串

[string1
deleteCharactersInRange:NSMakeRange(2,
2)];

NSLog(@"%@", string1);

NSString *p0 =
@"aBcD_EfGk";

if([p0
hasSuffix:@"EfGk"])

{NSString *p1 =
[p0
stringByReplacingOccurrencesOfString:@"EfGk"withString:@"WXYZ"];

NSString *p2 = [p1
lowercaseString];

NSLog(@"%@",p2);

}

//使用类方法创建NSString对象

NSString *string2
=
[NSStringstringWithFormat:@"蓝欧科技有限公司"];

NSLog(@"%@", string2);

//直接赋值

NSString *string3 =
@"abc";

NSLog(@"%@", string3);

//获取字符串长度

NSInteger string1Length
= [string1 length];

NSLog(@"%ld", string1Length);

NSInteger len2 =
[string2 length];

NSLog(@"%ld", len2);

//判断字符串前缀

BOOL result1= [string1
hasPrefix:@"m"];

NSLog(@"------%d", result1);

BOOL result2 = [string1
hasSuffix:@"年"];

NSLog(@"%d",result2);

//查找字符串位置

NSRange range1 =
[string2
rangeOfString:@"有"];

NSLog(@"位置：%ld 
长度：%ld", range1.location,
range1.length);

NSRange kk = [string2
rangeOfString:@"科技有"];

NSLog(@"weizhi:%ld 
lengt:%ld", kk.location,
kk.length);

//截取字符串

NSString *p =
[[string2
substringFromIndex:2]substringToIndex:4];

NSString *p1 = [string2
substringToIndex:4];

NSLog(@"~~~~~~~%@,
%@", p, p1);

//NSArray数组类

//1.使用实例方法创建数组

NSArray *array1 =
[[NSArrayalloc]initWithObjects:@"1",@"2",@"3",
nil];

NSLog(@"%@", array1);

//2.使用类方法创建数组

NSArray *array2 =
[NSArrayarrayWithObjects:@"4",@"5",@"6",
nil];

NSLog(@"%@", array2);

//3.获取数组元素个数

NSUInteger count =
[array1 count];

NSLog(@"%ld", count);

//4.根据索引值获取对象

NSString *p = [array1
objectAtIndex:1];

NSLog(@"%@", p);

//5.获取对象在数组中的索引值

NSUInteger index =
[array1 indexOfObject:@"3"];

NSLog(@"%ld", index);

//NSMutableArray数组类

//1.使用实例方法创建

NSMutableArray *m1
=
[[NSMutableArrayalloc]initWithObjects:@"a",@"b",@"c",
nil];

//2。使用类方法创建

NSMutableArray *m2
=
[NSMutableArrayarrayWithObjects:@"a",@"b",@"c",
nil];

//3.添加元素

[m1
addObject:@"d"];

NSLog(@"%@",m1);

//4.插入元素

[m1
insertObject:@"ZZ"atIndex:1];

NSLog(@"%@",m1);

//5.删除元素

[m1
removeObject:@"ZZ"];

NSLog(@"%@",m1);

//6.替换元素

[m1
replaceObjectAtIndex:2withObject:@"Ming"];

NSLog(@"%@", m1);

//7.交换指定位置的2个元素

[m1
exchangeObjectAtIndex:1withObjectAtIndex:2];

NSLog(@"%@", m1);

//8.根据对象来交换两个元素的位置

[m1
exchangeObjectAtIndex:[m1
indexOfObject:@"a"]
withObjectAtIndex:[m1
indexOfObject:@"Ming"]];

NSLog(@"%@",m1);

//9.遍历数组对象
（循环输出）

for (int i
= 0; i < [m1 count]; i ++) {

NSString
*m2 = [m1 objectAtIndex:i];

NSLog(@"普通遍历:%@",m2);

}

for
(NSString *str  in m1) {

NSLog(@"快速遍历:%@",str);

}

NSMutableArray
*book =
[NSMutableArrayarrayWithObjects:@"AAA",@"BBB",@"CCC",@"DDD",
nil];

[book
addObject:@"MMM"];

[book
removeObject:@"CCC"];

[book
replaceObjectAtIndex:0withObject:@"WWW"];

NSUInteger i =
[book
indexOfObject:@"BBB"];

NSString *p1 = [book
objectAtIndex:i];

NSLog(@"%@", p1);

for
(NSString *list  in book) {

NSLog(@"%@",list);

}

NSLog(@"%@", book);

NSMutableArray *n
=
[NSMutableArrayarrayWithObjects:@"1",@"2",@"3",
nil];

NSNumber *num =
[NSNumbernumberWithFloat:4.4];

NSLog(@"%@",num);

[n addObject:num];

NSLog(@"%@",n);

NSNumber *n1 = [n
objectAtIndex:3];

NSLog(@"%@",n1);

CGFloat n2 = [n1
intValue];

NSLog(@"%.2lf",n2);

NSRange p2 =
NSMakeRange(4, 4);

NSString *p3 =
[string2
substringWithRange:NSMakeRange(2,4)];

NSLog(@"%@", p3);

//拼接

NSString *p4 =
[string2
stringByAppendingString:@"123"];

NSLog(@"%@",p4);

//替换

NSString *p5 =
[string2
stringByReplacingOccurrencesOfString:@"蓝欧"withString:@"abcdef"];

NSLog(@"%@", p5);

//比较

NSString *p6 =
@"a";

NSString *p7 =
@"B";

NSComparisonResult
result3 = [p6 compare:p7];

NSLog(@"%ld",result3);

NSString NSArray和可变字符串、数组的用法,布布扣,bubuko.com