IOS NSPredicate 查询、搜索

IOS NSPredicate 查询、搜索
简述:Cocoa框架中的NSPredicate用于查询,原理和用法都类似于SQL中的where,作用相当于数据库的过滤取。

最常用到的函数

  • (NSPredicate *)predicateWithFormat:(NSString *)predicateFormat, ...;
    1.比较运算符 > 、< 、== 、 >= 、<= 、 !=
    例:@"number >= 99"

2.范围运算符:IN 、BETWEEN
例:@"number BETWEEN {1,5}"
@"address IN {'shanghai','nanjing'}"

3.字符串本身:SELF
例:@"SELF == 'APPLE'"

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。

5.通配符:LIKE
例:@"name LIKE[cd] 'er'" //代表通配符,Like也接受[cd].
@"name LIKE[cd] '???er
'"

6.正则表达式:MATCHES
例:NSString *regex = @"^A.+e$"; //以A开头,e结尾
@"name MATCHES %@",regex

实际应用:对NSArray进行过滤

NSArray *array = [[NSArray alloc]initWithObjects:@"beijing",@"shanghai",@"guangzou",@"wuhan", nil];
NSString *string = @"ang";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF CONTAINS %@",string];
NSLog(@"%@",[array filteredArrayUsingPredicate:pred]);

实际应用:判断字符串首字母是否为字母

NSString *regex = @"[A-Za-z]+";
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];

if ([predicate evaluateWithObject:aString]) {
}

实际应用:字符串替换

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NSError* error = NULL;
NSRegularExpression* regex = [NSRegularExpression regularExpressionWithPattern:@"(encoding=")[^"]+(")"
options:0
error:&error];
NSString* sample = @"<xml encoding="abc"></xml><xml encoding="def"></xml><xml encoding="ttt"></xml>";
NSLog(@"Start:%@",sample);
NSString* result = [regex stringByReplacingMatchesInString:sample
options:0
range:NSMakeRange(0, sample.length)
withTemplate:@"$1utf-8$2"];
NSLog(@"Result:%@", result);
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实际应用:截取字符串

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//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);  
}  

}
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实际应用:判断手机号码,电话号码函数

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// 正则判断手机号码地址格式

  • (BOOL)isMobileNumber:(NSString )mobileNum
    {
    /
    *
    * 手机号码
    * 移动:134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188
    * 联通:130,131,132,152,155,156,185,186
    * 电信:133,1349,153,180,189
    /
    NSString * MOBILE = @"^1(3[0-9]|5[0-35-9]|8[025-9])\d{8}$";
    /
    *
    10 * 中国移动:China Mobile
    11 * 134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188
    12 /
    NSString * CM = @"^1(34[0-8]|(3[5-9]|5[017-9]|8[278])\d)\d{7}$";
    /
    *
    15 * 中国联通:China Unicom
    16 * 130,131,132,152,155,156,185,186
    17 /
    NSString * CU = @"^1(3[0-2]|5[256]|8[56])\d{8}$";
    /
    *
    20 * 中国电信:China Telecom
    21 * 133,1349,153,180,189
    22 /
    NSString * CT = @"^1((33|53|8[09])[0-9]|349)\d{7}$";
    /
    *
    25 * 大陆地区固话及小灵通
    26 * 区号:010,020,021,022,023,024,025,027,028,029
    27 * 号码:七位或八位
    28 */
    // NSString * PHS = @"^0(10|2[0-5789]|\d{3})\d{7,8}$";

    NSPredicate *regextestmobile = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", MOBILE];
    NSPredicate *regextestcm = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CM];
    NSPredicate *regextestcu = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CU];
    NSPredicate *regextestct = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CT];

    if (([regextestmobile evaluateWithObject:mobileNum] == YES)
    || ([regextestcm evaluateWithObject:mobileNum] == YES)
    || ([regextestct evaluateWithObject:mobileNum] == YES)
    || ([regextestcu evaluateWithObject:mobileNum] == YES))
    {
    if([regextestcm evaluateWithObject:mobileNum] == YES) {
    NSLog(@"China Mobile");
    } else if([regextestct evaluateWithObject:mobileNum] == YES) {
    NSLog(@"China Telecom");
    } else if ([regextestcu evaluateWithObject:mobileNum] == YES) {
    NSLog(@"China Unicom");
    } else {
    NSLog(@"Unknow");
    }

      return YES;
    

    }
    else
    {
    return NO;
    }
    }
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实际应用:邮箱验证、电话号码验证

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//是否是有效的正则表达式

+(BOOL)isValidateRegularExpression:(NSString *)strDestination byExpression:(NSString *)strExpression

{

NSPredicate *predicate = [NSPredicatepredicateWithFormat:@"SELF MATCHES %@", strExpression];

return [predicate evaluateWithObject:strDestination];

}

//验证email
+(BOOL)isValidateEmail:(NSString *)email {

NSString *strRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{1,5}";

BOOL rt = [CommonTools isValidateRegularExpression:email byExpression:strRegex];

return rt;

}

//验证电话号码
+(BOOL)isValidateTelNumber:(NSString *)number {

NSString *strRegex = @"[0-9]{1,20}";

BOOL rt = [CommonTools isValidateRegularExpression:number byExpression:strRegex];

return rt;

}
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实际应用:NSDate进行筛选

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//日期在十天之内:
NSDate endDate = [[NSDate date] retain];
NSTimeInterval timeInterval= [endDate timeIntervalSinceReferenceDate];
timeInterval -=3600
24*10;
NSDate *beginDate = [[NSDate dateWithTimeIntervalSinceReferenceDate:timeInterval] retain];
//对coredata进行筛选(假设有fetchRequest)
NSPredicate *predicate_date =
[NSPredicate predicateWithFormat:@"date >= %@ AND date <= %@", beginDate,endDate];

[fetchRequest setPredicate:predicate_date];
//释放retained的对象
[endDate release];
[beginDate release];
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