- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
/**
*NSPredicate 的相关用法
*/
[self testPredicateDefinition];
[self testPredicateComparation];
[self testPredicateRange];
[self testPredicateComparationToSelf];
[self testPredicateRelateToNSString];
[self testPredicateWildcard];
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
[self.navigationController pushViewController:[[ThirdViewController alloc] init] animated:YES];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:YES];
// self.tabBarController.tabBar.hidden = NO;
}
#pragma mark - 1. 熟悉Predicate
- (void)testPredicateDefinition{
NSArray *array1 = [NSArray arrayWithObjects:@1,@2,@3,@5,@5,@6,@7, nil];
NSArray *array2 = [NSArray arrayWithObjects:@4,@5, nil];
//1. **** SELF in ****
NSPredicate *predicate1 = [NSPredicate predicateWithFormat:@"SELF in %@",array2];
NSArray *temp1 = [array1 filteredArrayUsingPredicate:predicate1];
// 表示筛选array1在array2中的元素!YES！其中SELF指向filteredArrayUsingPredicate的调用者。
[temp1 enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"temp1 = %@",obj);
}];
/*
2016-06-02 14:54:29.854 3D Touch[5146:156676] temp1 = 5
2016-06-02 14:54:29.854 3D Touch[5146:156676] temp1 = 5
*/
NSPredicate *predicate2 = [NSPredicate predicateWithFormat:@"SELF in %@",array1];
NSArray *temp2 = [array2 filteredArrayUsingPredicate:predicate2];
// 表示筛选array2在array1中的元素!YES！其中SELF指向filteredArrayUsingPredicate的调用者。
[temp2 enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"temp2 = %@",obj);
}];
/*
2016-06-02 14:54:29.854 3D Touch[5146:156676] temp2 = 5
*/
}
#pragma mark - 2.测试Predicate的比较功能
- (void)testPredicateComparation{
/*
(1)比较运算符>,<,==,>=,<=,!=
可用于数值及字符串
例：@"number > 100"
*/
NSArray *array = [NSArray arrayWithObjects:@1,@2,@3,@4,@5,@2,@6, nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF > 4"];
/*
NSArray *array = [NSArray arrayWithObjects:@"1",@"3",@"5",@"7",@"9",@"11",@"12", nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"number > 4"];//错误
*/
NSArray *fliterArray = [array filteredArrayUsingPredicate:predicate];
[fliterArray enumerateObjectsWithOptions:NSEnumerationConcurrent usingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"测试Predicate的比较功能 fliterArray = %@",obj);
}];
}
#pragma mark - 3. Predicate范围运算功能
- (void)testPredicateRange{
/*
(2)范围运算符：IN、BETWEEN
例：@"number BETWEEN {1,5}"
@"address IN {'shanghai','beijing'}"
*/
NSArray *array = [NSArray arrayWithObjects:@1,@2,@3,@4,@5,@2,@6, nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF in {2,5,1}"];// 找到 in 的意思是array中{1,2,5}的元素
// NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF BETWEEN {2,5}"];// 找到 BETWEEN 的意思是array中 （2 - 5） 区间 的元素
NSArray *fliterArray = [array filteredArrayUsingPredicate:predicate];
[fliterArray enumerateObjectsWithOptions:NSEnumerationConcurrent usingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"Predicate范围运算功能 fliterArray = %@",obj);
}];
}
#pragma mark 4. Predicate 与自身相比的功能
- (void)testPredicateComparationToSelf{
/*
(3)字符串本身:SELF
例：@“SELF == ‘APPLE’"
*/
NSArray *placeArray = [NSArray arrayWithObjects:@"Shanghai",@"Hangzhou",@"Beijing",@"Macao",@"Taishan", nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF == 'Beijing'"];
NSArray *tempArray = [placeArray filteredArrayUsingPredicate:predicate];
[tempArray enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"Predicate 与自身相比的功能 obj == %@",obj);
}];
}
// @"name CONTAIN[cd] 'ang'" <实际应用：对NSArray进行过滤>
#pragma mark 5. Predicate 字符串相关：BEGINSWITH、ENDSWITH、CONTAINS
- (void)testPredicateRelateToNSString{
/*
(4)字符串相关：BEGINSWITH、ENDSWITH、CONTAINS
例：@"name CONTAIN[cd] 'ang'" //包含某个字符串
@"name BEGINSWITH[c] 'sh'" //以某个字符串开头
@"name ENDSWITH[d] 'ang'" //以某个字符串结束
注:[c]不区分大小写[d]不区分发音符号即没有重音符号[cd]既不区分大小写，也不区分发音符号。
*/
NSArray *placeArray = [NSArray arrayWithObjects:@"Shanghai",@"Hangzhou",@"Beijing",@"Macao",@"Taishan", nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF CONTAINS [cd] 'an' "];
// NSPredicate *predicate1 = [NSPredicate predicateWithFormat:@"SELF Beginswith [cd] 'sh' "];
NSArray *tempArray = [placeArray filteredArrayUsingPredicate:predicate];
[tempArray enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"Predicate 字符串相关：BEGINSWITH、ENDSWITH、CONTAINS obj == %@",obj);
}];
}
#pragma mark 6. Predicate 的通配
- (void)testPredicateWildcard{
/*
(5)通配符：LIKE
例：@"name LIKE[cd] '*er*'"
// *代表通配符,Like也接受[cd].
@"name LIKE[cd] '???er*'"
*/
NSArray *placeArray = [NSArray arrayWithObjects:@"Shanghai",@"Hangzhou",@"Beijing",@"Macao",@"Taishan", nil];
// NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF like '*ai*' "];
NSString *str = [NSString stringWithFormat:@"SELF like '*%@*' ",@"ai"];
NSPredicate *predicate = [NSPredicate predicateWithFormat:str];
// NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name LIKE[cd] '???er*'"];//不知道为什么报错
NSArray *tempArray = [placeArray filteredArrayUsingPredicate:predicate];
[tempArray enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"obj == %@",obj);
}];
[self testPredicateRegex];
[self testThid];
}
//1)对NSArray进行过滤
- (void)testOne
{
NSArray *array = [[NSArray alloc]initWithObjects:@"beijing",@"shanghai",@"guangzou",@"wuhan", nil];
NSString *string = @"ang";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF CONTAINS %@",string];
NSLog(@"%@",[array filteredArrayUsingPredicate:pred]);
}
//(2)判断字符串首字母是否为字母:
- (void)testPredicateRegex {
/*
(6)正则表达式：MATCHES
例：NSString *regex = @"^A.+e$"; //以A开头，e结尾
@"name MATCHES %@",regex
*/
NSString *regex = @"[A-Za-z]+";
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
BOOL isMATCHES = [predicate evaluateWithObject:@"1ddadfa"];
if (isMATCHES) {
NSLog(@"isMATCHES = %d",isMATCHES);
}
}
//(3)字符串替换
- (void)testThid
{
//组装一个字符串，需要把里面的网址解析出来
NSString *urlString=@"<meta/><link/><title>1Q84 BOOK1</title></head><body>";
//NSRegularExpression类里面调用表达的方法需要传递一个NSError的参数。下面定义一个
NSError *error;
//http+:[^\\s]* 这个表达式是检测一个网址的。(?<=title\>).*(?=</title)截取html文章中的<title></title>中内文字的正则表达式
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?<=title\\>).*(?=</title)" options:0 error:&error];
if (regex != nil) {
NSTextCheckingResult *firstMatch=[regex firstMatchInString:urlString options:0 range:NSMakeRange(0, [urlString length])];
if (firstMatch) {
NSRange resultRange = [firstMatch rangeAtIndex:0];
//从urlString当中截取数据
NSString *result=[urlString substringWithRange:resultRange];
//输出结果
NSLog(@"->%@<-",result);
}
}
}