如何从 NSString 获取特定的字符串？

Question

我有一个字符串，例如：

Sodium Nitrite E250 is a food additive that gives cured meats, such as ham E103, bacon, hot dogs, frankfurters, smoked fish E1255 corned beef, their characteristic red colour and flavour.

我需要从以下位置获取元素的 NSArray：E250、E103、E1255上面的文本并与我预定义的 NSArray(E100, E101,...E1500) 元素进行比较有什么办法吗？

Answer 1

与其从文本中提取字符串，我建议您从数组中查找模板，例如：

NSString *input = @"Sodium Nitrite E250 is a food additive ...";
for (NSString *str in @[ @"E100", @"E101", @"E1500" ])
    if ([input rangeOfString:str].location != NSNotFound) {
        // do something
    }

Answer 2

尝试使用此代码

NSArray *ary = [NSArray arrayWithObjects:@"E250", nil]; // String Data to find in String
NSMutableArray *aryFoundData = [[NSMutableArray alloc]init];

for (int i=0; i<ary.count; i++) {
    NSString *str = @"Your String E250";
    if ([str containsString:[ary objectAtIndex:i]]) {
        [aryFoundData addObject:[ary objectAtIndex:i]];
    }
}

// Now aryFoundData contains all the data which are available in string

希望对您有所帮助。

Answer 3

看看这个：

NSString *testString = @"Sodium Nitrite E250 is a food additive that gives cured meats, such as ham E103, bacon, hot dogs, frankfurters, smoked fish E1255 corned beef, their characteristic red colour and flavour.";

NSRegularExpression *regex = [[NSRegularExpression alloc] initWithPattern:@"E\d+" options:0 error:nil];

[regex enumerateMatchesInString:testString options:0 range:NSMakeRange(0, testString.length) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
    NSLog(@"%@", [testString substringWithRange:result.range]);
}];

它记录以下内容：

2015-05-05 15:12:55.898 标签[3649:339896] E250

2015-05-05 15:12:55.898 标签[3649:339896] E103

2015-05-05 15:12:55.898 标签[3649:339896] E1255

Answer 4

请尝试以下逻辑，这可能会解决您的问题。

NSMutableArray *ar = [NSMutableArray new];
NSString *str = @"Sodium Nitrite E250 is a food additive that gives cured meats, such as ham E103, bacon, hot dogs, frankfurters, smoked fish E1255 corned beef, their characteristic red colour and flavour.";

NSArray * words = [str componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
for (NSString * word in words) {
    if ([word length] > 0) {
        NSString * firstLetter = [word substringToIndex:1];
        if ([firstLetter isEqualToString:@"E"]) {
            [ar addObject:word];
        }
    }
}
NSLog(@"%@",ar);

Answer 5

如您所说，您想与现有的数组元素进行比较。所以你可以做下面的..

NSArray *array = @[@"E100", @"E250", @"E103", @"E200", .....];
NSString *myString = @"Sodium Nitrite E250 is a food additive that gives cured meats, such as ham E103, bacon, hot dogs, frankfurters, smoked fish E1255 corned beef, their characteristic red colour and flavour.";

[array enumerateObjectsUsingBlock:^(NSString *objectString, NSUInteger idx, BOOL *stop) {
    if([myString rangeOfString:objectString].location != NSNotFound) {
        NSLog(@"%@ - found", objectString);
    }
    else {
        NSLog(@"%@ - Not found", objectString);
    }
}];

Answer 6

您可以通过执行以下操作从 NSString 获取特定关键字并将它们添加到 NSMutableArray。

 NSString* strText = @"Sodium Nitrite E250 is a food additive that gives cured meats, such as ham E103, bacon, hot dogs, frankfurters, smoked fish E1255 corned beef, their characteristic red colour and flavour.";
    __block NSMutableArray* arrayStoreRange = [NSMutableArray new];

    //To Find Image from HTML string and add renge in NSMutableArray
    //width
    NSRegularExpression* tableRegex = [[NSRegularExpression alloc] initWithPattern:@"E\w*\d" options:0 error:NULL] ;
    [tableRegex enumerateMatchesInString:strText options:0 range:NSMakeRange(0, [strText length]) usingBlock:^(NSTextCheckingResult *match, NSMatchingFlags flags, BOOL *stop){

        [arrayStoreRange addObject:[strText substringWithRange:match.range]];

    }];

    NSLog(@"Output : %@",arrayStoreRange);

    for (NSString *str in arrayStoreRange){

        if ([yourArray containsObject:str]) {
            // do something
            NSLog(@"Object found");
        }
        else{
            NSLog(@"Object  not found");
        }
    }

输出：

Output : (
    E250,
    E103,
    E1255
)

希望对您有所帮助。

如何从 NSString 获取特定的字符串？

How to get specific strings from NSString?

search

objective-c

nsstring

nsarray

ios