向字典2对象中添加整个字典对象3
[dic2 addEntriesFromDictionary:dic3];
/*----------创建字典----------------------*/
- (id) initWithObjectsAndKeys;
NSDictionary *dictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"One",@"1",@"Two",@"2",@"Three",@"3",nil];
NSString *string = [dictionary objectForKey:@"One"];
NSLog(@"string:%@",string);
NSLog(@"dictionary:%@",dictionary);
[dictionary release];
NSMutableDictionary
/*--------------创建可变字典----------------------*/
创建
NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
添加字典
[dictionary setObject:@"One" forKey:@"1"];
[dictionary setObject:@"Two" forKey:@"2"];
[dictionary setObject:@"Three" forKey:@"3"];
[dictionary setObject:@"Four" forKey:@"4"];
NSLog(@"dictionary:%@",dictionary);
删除指定的字典
[dictionary removeObjectForKey:@"3"];
NSLog(@"dictionary:%@",dictionary);
NSValue（对任何对象进行包装）
/*-------------将NSRect放入NSArray中---------------*/
将NSRect放入NSArray中
NSMutableArray *array = [[NSMutableArray alloc] init];
NSValue *value;
CGRect rect = CGRectMake(0, 0, 320, 480);
value = [NSValue valueWithBytes:&rect objCType:@encode(CGRect)];
[array addObject:value];
NSLog(@"array:%@",array);
从Array中提取
value = [array objectAtIndex:0];
[value getValue:&rect];
NSLog(@"value:%@",value);
从目录搜索扩展名为jpg的文件
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *home;
home = @"../Users/";
NSDirectoryEnumerator *direnum;
direnum = [fileManager enumeratorAtPath: home];
NSMutableArray *files = [[NSMutableArray alloc] init];
枚 举
NSString *filename;
while (filename = [direnum nextObject]) {
if([[filename pathExtension] hasSuffix:@"jpg"]){
[files addObject:filename];
}
}
快速枚举
for(NSString *filename in direnum)
{
if([[filename pathExtension] isEqualToString:@"jpg"]){
[files addObject:filename];
}
}
NSLog(@"files:%@",files);
枚举
NSEnumerator *filenum;
filenum = [files objectEnumerator];
while (filename = [filenum nextObject]) {
NSLog(@"filename:%@",filename);
}
快速枚举
for(id object in files)
{
NSLog(@"object:%@",object);
}
只判断指针数值，而不是它们所指向的内容
*/
if(thing1==thing2){
NSLog(@"== same");
}
/*
compare:比较两个字符串。区分大小写
compare将接收 对象和传递来的字符串逐个字符的进行比较，它返回一个NSComparisonResult(枚举类 型)来显示结果。
typedef enum _NSComparisonResult{
NSOrderedAscending=-1;
NSOrderedsame;
NSOrderedDescending;
} NSComparisonResult;
*/
[thing1 compare:thing2];
if(NSOrderedSame==[thing1 compare:thing2]){
NSLog(@"compare same");
}
compare：options:
/***
-(NSComparisonResult) compare:(NSString *) string
options:(unsinged) mask;
options 是一个位掩 码，可以使用|添加选项标记
选 项：
NSCaseInsensitiveSearch:不区分大小写字符
NSLiteralSearch:进行完全比较，区分大小写
NSNumbericSearch:比较字符串的字符个数，而不是字符值
*/
if([thing1 compare:thing2 options:NSCaseInsensitiveSearch|
NSNumericSearch]==NSOrderedSame){
NSLog(@"they match");
}
删 除字符串
-(void) deleteCharactersInRange:(Rangerange;
NSMutableString *ms;
ms=[NSMutableString stringWithCapacity:50];
[ms appendString:@"aabbccdd"];
NSRange range;
range=[ms rangeOfString:@"cc"];
[ms deleteCharactersInRange:range];
NSLog(ms);
------------切分 数组
-componentsSeparatedByString:
NSString *ns=@"sdf,dsfs,dfd,fdf,df,dd";
NSArray *comArr=[ns componentsSeparatedByString:@","];
for(int i=0;i<[comArr count];i++){
NSLog(@"componentsSeparatedByString===%@",[comArr objectAtIndex:i]);
}
componentJoinedByString: 合并nsarray中的元素来创建字符串
NSString *joinedStr=[comArr componentsJoinedByString:@"-->"];
NSLog(@"joined---= %@",joinedStr);
各种数值，NSNumber NSValue
/*
cocoa 提供了NSNumber类来包装基本数据类型
+(NSNumber *) numberWithChar:(char) value;
+(NSNumber *) numberWithInt:(int) value;
+(NSNumber *) numberWithFloat:(float) value;
+(NSNumber *) numberWthiBool:(BOOL) value;
-(char) charValue;
-(int) intVlaue;
-(float) floatValue;
-(BOOL) boolValue;
-(NSString *) stringValue;
**/
NSNumber *number;
number=[NSNumber numberWithInt:3];
[mutableDic setObject:number forKey:@"int"];
int num=[[mutableDic objectForKey:@"int"] intValue];
NSLog(@"int object value== %d",num);
NSValue .NSNumber实际上是NSValue的子类，NSValue可以包装任意值
/**
+(NSValue *) valueWithBytes:(const void *) value objCType:(const char *) type;
传递的参数是你想要包装的数值的地址，通常，得到的是你想要存储的变量的地址（在c语言里适用操作符 & ），你也可以提供一个描述这个数据类型的字符串，通常用来说明struct中实体的类型和大小。你不用自己写代码
来生成这个字符串，@encode编译器指令可以接受数据类型的名称并为你生成合适的字符串
*/
NSRect rect= NSMakeRect(1, 2, 30, 40);
NSValue *value;
value=[NSValue valueWithBytes:&rect objCType:@encode(NSRect)];
NSMutableArray *mr=[NSMutableArray arrayWithCapacity:50];
[mr addObject:value];
getValue 提取 数据
/**
-(void) getValue:(void *) value; 要传递的是存储这个数值的变量的地址
*/
/***
value=[mr objectAtIndex:0];
NSRect r;
NSLog(@"00000 ===%@",r);
[value getValue:&r];
NSLog(@"111== %@",r);
*/
/**
+(NSValue *) valueWithPoint:(NSPoint) point;
+(NSValue *) valueWithSize:(NSSize) size;
+(NSValue *) valueWithRect:(NSRect) rect;
-(NSPoint) pointValue;
-(NSSize) sizeValue;
-(NSRect) rectValue;
*/
NSNull
/*
*+(NSNull *) null;
*/
[mutableDic setObject:[NSNull null] forKey:@"fax"];
id fax;
fax=[mutableDic objectForKey:@"fax"];
if(fax==[NSNull null]){
NSLog(@"pppppppppppppppppp");
}
[pool drain];
return 0;