objective-c之谓词

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// main.m

// NSPredicateDemo

// Created by qingyun on 15/12/18.

#import <Foundation/Foundation.h>

#import "Person.h"

int main(int argc,const char * argv[]) {

@autoreleasepool {

//用来查询和过滤类似于SQL数据库中的where

NSArray *array=@[@111,@323,@35,@345,@67];

NSLog(@"原始数组：%@",array);

//1.创建一个谓词对象：指定筛选条件

NSLog(@"\n================谓词使用运算符================");

//过滤数组大于100的对象

NSPredicate *predicate=[NSPredicatepredicateWithFormat:@"SELF>100"];//SELF本身代表被过滤的数组中的每一个对象本身支持所有的关系运算符（> >= < <= == !=）

NSArray *fltarray=[arrayfilteredArrayUsingPredicate:predicate];

NSLog(@"数组中大于100的数字有：%@",fltarray);

//评估单个对象

NSNumber *num=@234;

BOOL reesult=[predicateevaluateWithObject:num];//num是否满足之前定义的条件

NSLog(@"%d",reesult);

NSLog(@"\n================谓词对数组的使用================");

//创建Person类对象的数组

Person *p1=[[Personalloc]initWithName:@"listen"andAge:20];

Person *p2=[[Personalloc]initWithName:@"to"andAge:21];

Person *p3=[[Personalloc]initWithName:@"rain"andAge:22];

Person *p4=[[Personalloc]initWithName:@"lgeg"andAge:23];

Person *p5=[[Personalloc]initWithName:@"bao"andAge:24];

Person *p6=[[Personalloc]initWithName:@"bao1"andAge:24];

NSArray *personArray=@[p1,p2,p3,p4,p5,p6];

NSLog(@"过滤之前的：%@",personArray);

//谓词是基于KVC机制的可以通过属性对应的字符串来标示想要访问的属性

predicate=[NSPredicatepredicateWithFormat:@"self.name=='listen'"];

//对数组施加谓词规则

NSLog(@"\n================对数组施加谓词规则================");

NSArray *fltPerson=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson满足条件的是：%@",fltPerson);

predicate=[NSPredicatepredicateWithFormat:@"self.age<22"];

NSArray *fltPerson1=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson1满足条件的是：%@",fltPerson1);

//同时满足多个条件支持逻辑与或非（&&==and）（||==OR）(!==not)

NSLog(@"\n================同时满足多个条件（与或非）================");

predicate=[NSPredicatepredicateWithFormat:@"self.name=='listen'||self.age>22"];

NSArray *fltPerson2=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson2满足条件的是：%@",fltPerson2);

predicate=[NSPredicatepredicateWithFormat:@"!self.name=='listen'&&self.age<22"];

NSArray *fltPerson3=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson3满足条件的是：%@",fltPerson3);

//访问对象属性时 self.可以省略但是如果是用对象本身的值（比如NSNumber类的对象）时，要用SELF

//BEGINSWITH （以xxxx开头） ENDsWITH (以xxx结尾) CONTAINS （包含xxx）

//[cd]中的c是不区分大小写 d是不区分重音符号

NSLog(@"\n================BEGINSWITH ENDsWITH CONTAINS================");

predicate=[NSPredicatepredicateWithFormat:@"name BEGINSWITH[cd] 'l'"];

NSArray *fltPerson4=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson4满足条件的是：%@",fltPerson4);

predicate=[NSPredicatepredicateWithFormat:@"name endswith 'o'"];

NSArray *fltPerson5=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson5满足条件的是：%@",fltPerson5);

predicate=[NSPredicatepredicateWithFormat:@"name contains 'e'"];

NSArray *fltPerson6=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson6满足条件的是：%@",fltPerson6);

//IN(指定离散的范围只和{}中的值匹配) BETWEEN(指定一个闭区间范围{num1，num2}表示num1~num2之间的值)

NSLog(@"\n================取范围================");

predicate=[NSPredicatepredicateWithFormat:@"age IN {22,24}"];

NSArray *fltPerson7=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson7满足条件的是：%@",fltPerson7);

predicate=[NSPredicatepredicateWithFormat:@"age between {22,24}"];

NSArray *fltPerson8=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson8满足条件的是：%@",fltPerson8);

//ALL（所有的都满足） ANY（至少有一个满足）施加的是集合对象

NSLog(@"\n================all和any================");

predicate =[NSPredicatepredicateWithFormat:@"all age>22"];

BOOL result1=[predicateevaluateWithObject:personArray];

if (result1) {

NSLog(@"所有人年龄都大于22");

}

else

{

NSLog(@"有不满二十岁的");

}

predicate =[NSPredicatepredicateWithFormat:@"any age>22"];

BOOL result2=[predicateevaluateWithObject:personArray];

if (result2) {

NSLog(@"至少有一个人大于22");

}

else

{

NSLog(@"所有的人都不满二十二岁");

}

NSLog(@"\n================谓词占位符================");

//%k是key的占位符只能在谓词中使用

NSString *key=@"name";

NSString *value=@"lgeng";

predicate =[NSPredicatepredicateWithFormat:@"%K==%@",key,value];

NSArray *fltPerson9=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson9满足条件的是：%@",fltPerson9);

//谓词中使用变量($NAME)

NSLog(@"\n================谓词模板================");

//先生成一个谓词模板

NSPredicate *predicateTempLate=[NSPredicatepredicateWithFormat:@"name==$NAME"];

//由谓词模板生成谓词

//1.创建一个字典

NSString *name=@"listen";

NSDictionary *dict=@{@"NAME":name};

//2.生成一个具体的谓词用字典中的Value 来取代模板的变量

predicate =[predicateTempLate predicateWithSubstitutionVariables:dict];

NSArray *fltPerson10=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson10满足条件的是：%@",fltPerson10);

predicateTempLate=[NSPredicatepredicateWithFormat:@"age between$RANGE"];

NSNumber *beginAge=@20;

NSNumber *endAge=@23;

dict=@{@"RANGE":@[beginAge,endAge]};

predicate=[predicateTempLate predicateWithSubstitutionVariables:dict];

NSArray *fltPerson11=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson11满足条件的是：%@",fltPerson11);

//谓词中使用通配符 like (*匹配多个字符)（？匹配单个字符但是可以叠加？？就是两个字符）

predicate=[NSPredicatepredicateWithFormat:@"name like'l*'"];

NSArray *fltPerson12=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson12满足条件的是：%@",fltPerson12);

predicate=[NSPredicatepredicateWithFormat:@"name like't?'"];

NSArray *fltPerson13=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson13满足条件的是：%@",fltPerson13);

predicate=[NSPredicatepredicateWithFormat:@"name like'?o'"];

NSArray *fltPerson14=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson14满足条件的是：%@",fltPerson14);

predicate=[NSPredicatepredicateWithFormat:@"name like'*n'"];

NSArray *fltPerson15=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson15满足条件的是：%@",fltPerson15);

//正则表达式matches

NSLog(@"\n================谓词正则表达式================");

predicate =[NSPredicatepredicateWithFormat:@"name matches '^l.*n$'"];

NSArray *fltPerson16=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson16满足条件的是：%@",fltPerson16);

predicate =[NSPredicatepredicateWithFormat:@"name matches '^ra.?n$'"];

NSArray *fltPerson17=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson17满足条件的是：%@",fltPerson17);

predicate =[NSPredicatepredicateWithFormat:@"name matches '^..*[1]$'"];

NSArray *fltPerson18=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson18满足条件的是：%@",fltPerson18);

predicate =[NSPredicatepredicateWithFormat:@"name matches '^.*$'"];

NSArray *fltPerson19=[personArrayfilteredArrayUsingPredicate:predicate];

NSLog(@"fltPerson19满足条件的是：%@",fltPerson19);

}

return 0;

}

打印结果

原始数组：(

111,

323,

35,

345,

)

================谓词使用运算符================

数组中大于100的数字有：(

111,

323,

345

)

================谓词对数组的使用================

过滤之前的：(

"name:listen age:20",

"name:to age:21",

"name:rain age:22",

"name:lgeg age:23",

"name:bao age:24",

"name:bao1 age:24"

)

================对数组施加谓词规则================

fltPerson满足条件的是：(

"name:listen age:20"

)

fltPerson1满足条件的是：(

"name:listen age:20",

"name:to age:21"

)

================同时满足多个条件（与或非）================

fltPerson2满足条件的是：(

"name:listen age:20",

"name:lgeg age:23",

"name:bao age:24",

"name:bao1 age:24"

)

fltPerson3满足条件的是：(

"name:to age:21"

)

================BEGINSWITH ENDsWITH CONTAINS================

fltPerson4满足条件的是：(

"name:listen age:20",

"name:lgeg age:23"

)

fltPerson5满足条件的是：(

"name:to age:21",

"name:bao age:24"

)

fltPerson6满足条件的是：(

"name:listen age:20",

"name:lgeg age:23"

)

================取范围================

fltPerson7满足条件的是：(

"name:rain age:22",

"name:bao age:24",

"name:bao1 age:24"

)

fltPerson8满足条件的是：(

"name:rain age:22",

"name:lgeg age:23",

"name:bao age:24",

"name:bao1 age:24"

)

================all和any================

有不满二十岁的

至少有一个人大于22

================谓词占位符================

fltPerson9满足条件的是：(

)

================谓词模板================

fltPerson10满足条件的是：(

"name:listen age:20"

)

fltPerson11满足条件的是：(

"name:listen age:20",

"name:to age:21",

"name:rain age:22",

"name:lgeg age:23"

)

fltPerson12满足条件的是：(

"name:listen age:20",

"name:lgeg age:23"

)

fltPerson13满足条件的是：(

"name:to age:21"

)

fltPerson14满足条件的是：(

"name:to age:21"

)

2015-12-18 17:55:41.463 NSPredicateDemo[1062:658668] fltPerson15满足条件的是：(

"name:listen age:20",

"name:rain age:22"

)

================谓词正则表达式================

fltPerson16满足条件的是：(

"name:listen age:20"

)

fltPerson17满足条件的是：(

"name:rain age:22"

)

fltPerson18满足条件的是：(

"name:bao1 age:24"

)

fltPerson19满足条件的是：(

"name:listen age:20",

"name:to age:21",

"name:rain age:22",

"name:lgeg age:23",

"name:bao age:24",

"name:bao1 age:24"

)

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