在 Objective-C 中标记/拆分 NSString 的最佳方法是什么？
ggarber
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277
在这里找到答案：
NSString *string = @"oop:ack:bork:greeble:ponies";
NSArray *chunks = [string componentsSeparatedByString: @":"];
于 2008-11-03T21:10:11.050 回答
32
每个人都提到过componentsSeparatedByString:，但您也可以使用CFStringTokenizer（记住 anNSString和CFString是可互换的）这也将标记自然语言（例如不会在空格上分割单词的中文/日文）。
于 2009-01-11T11:54:44.620 回答
21
如果您只想拆分字符串，请使用-[NSString componentsSeparatedByString:]. 对于更复杂的标记化，使用 NSScanner 类。
于 2008-11-04T06:55:01.180 回答
7
如果您的标记化需求更复杂，请查看我的开源 Cocoa String 标记/解析工具包：ParseKit：
对于使用分隔符字符（如':'）的简单字符串拆分，ParseKit 肯定是矫枉过正。但同样，对于复杂的标记化需求，ParseKit 非常强大/灵活。
另请参阅ParseKit 标记化文档。
于 2008-11-06T02:33:35.590 回答
6
如果要标记多个字符，可以使用 NSString 的componentsSeparatedByCharactersInSet. NSCharacterSet 有一些方便的预制集合，例如whitespaceCharacterSet和illegalCharacterSet. 它有 Unicode 范围的初始化器。
您还可以组合字符集并使用它们进行标记，如下所示：
// Tokenize sSourceEntityName on both whitespace and punctuation.
NSMutableCharacterSet *mcharsetWhitePunc = [[NSCharacterSet whitespaceAndNewlineCharacterSet] mutableCopy];
[mcharsetWhitePunc formUnionWithCharacterSet:[NSCharacterSet punctuationCharacterSet]];
NSArray *sarrTokenizedName = [self.sSourceEntityName componentsSeparatedByCharactersInSet:mcharsetWhitePunc];
[mcharsetWhitePunc release];
请注意，componentsSeparatedByCharactersInSet如果连续遇到多个 charSet 成员，则会生成空白字符串，因此您可能需要测试长度小于 1。
于 2012-08-28T00:00:33.287 回答
5
于 2014-03-31T12:08:54.007 回答
2
If you are looking for splitting linguistic feature's of a string (Words, paragraphs, characters, sentences and lines), use string enumeration:
NSString * string = @" \n word1! word2,%$?'/word3.word4 ";
[string enumerateSubstringsInRange:NSMakeRange(0, string.length)
options:NSStringEnumerationByWords
usingBlock:
^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
NSLog(@"Substring: '%@'", substring);
}];
// Logs:
// Substring: 'word1'
// Substring: 'word2'
// Substring: 'word3'
// Substring: 'word4'
This api works with other languages where spaces are not always the delimiter (e.g. Japanese). Also using NSStringEnumerationByComposedCharacterSequences is the proper way to enumerate over characters, since many non-western characters are more than one byte long.
于 2014-08-03T15:07:39.830 回答
0
我有一个案例，我必须在使用 ldapsearch 进行 LDAP 查询后拆分控制台输出。首先设置并执行 NSTask（我在这里找到了一个很好的代码示例：Execute a terminal command from a Cocoa app）。但后来我不得不拆分和解析输出，以便仅从 Ldap-query-output 中提取打印服务器名称。不幸的是，这是相当乏味的字符串操作，如果我们用简单的 C 数组操作来操作 C 字符串/数组，这根本就没有问题。所以这是我使用可可对象的代码。如果您有更好的建议，请告诉我。
//as the ldap query has to be done when the user selects one of our Active Directory Domains
//(an according comboBox should be populated with print-server names we discover from AD)
//my code is placed in the onSelectDomain event code
//the following variables are declared in the interface .h file as globals
@protected NSArray* aDomains;//domain combo list array
@protected NSMutableArray* aPrinters;//printer combo list array
@protected NSMutableArray* aPrintServers;//print server combo list array
@protected NSString* sLdapQueryCommand;//for LDAP Queries
@protected NSArray* aLdapQueryArgs;
@protected NSTask* tskLdapTask;
@protected NSPipe* pipeLdapTask;
@protected NSFileHandle* fhLdapTask;
@protected NSMutableData* mdLdapTask;
IBOutlet NSComboBox* comboDomain;
IBOutlet NSComboBox* comboPrinter;
IBOutlet NSComboBox* comboPrintServer;
//end of interface globals
//after collecting the print-server names they are displayed in an according drop-down comboBox
//as soon as the user selects one of the print-servers, we should start a new query to find all the
//print-queues on that server and display them in the comboPrinter drop-down list
//to find the shares/print queues of a windows print-server you need samba and the net -S command like this:
// net -S yourPrintServerName.yourBaseDomain.com -U yourLdapUser%yourLdapUserPassWord -W adm rpc share -l
//which dispalays a long list of the shares
- (IBAction)onSelectDomain:(id)sender
{
static int indexOfLastItem = 0; //unfortunately we need to compare this because we are called also if the selection did not change!
if ([comboDomain indexOfSelectedItem] != indexOfLastItem && ([comboDomain indexOfSelectedItem] != 0))
{
indexOfLastItem = [comboDomain indexOfSelectedItem]; //retain this index for next call
//the print-servers-list has to be loaded on a per univeristy or domain basis from a file dynamically or from AN LDAP-QUERY
//initialize an LDAP-Query-Task or console-command like this one with console output
/*
ldapsearch -LLL -s sub -D "cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com" -h "yourLdapServer.com" -p 3268 -w "yourLdapUserPassWord" -b "dc=yourBaseDomainToSearchIn,dc=com" "(&(objectcategory=computer)(cn=ps*))" "dn"
//our print-server names start with ps* and we want the dn as result, wich comes like this:
dn: CN=PSyourPrintServerName,CN=Computers,DC=yourBaseDomainToSearchIn,DC=com
*/
sLdapQueryCommand = [[NSString alloc] initWithString: @"/usr/bin/ldapsearch"];
if ([[comboDomain stringValue] compare: @"firstDomain"] == NSOrderedSame) {
aLdapQueryArgs = [NSArray arrayWithObjects: @"-LLL",@"-s", @"sub",@"-D", @"cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com",@"-h", @"yourLdapServer.com",@"-p",@"3268",@"-w",@"yourLdapUserPassWord",@"-b",@"dc=yourFirstDomainToSearchIn,dc=com",@"(&(objectcategory=computer)(cn=ps*))",@"dn",nil];
}
else {
aLdapQueryArgs = [NSArray arrayWithObjects: @"-LLL",@"-s", @"sub",@"-D", @"cn=yourLdapUser,ou=yourOuWithLdapUserAccount,dc=yourDomain,dc=com",@"-h", @"yourLdapServer.com",@"-p",@"3268",@"-w",@"yourLdapUserPassWord",@"-b",@"dc=yourSecondDomainToSearchIn,dc=com",@"(&(objectcategory=computer)(cn=ps*))",@"dn",nil];
}
//prepare and execute ldap-query task
tskLdapTask = [[NSTask alloc] init];
pipeLdapTask = [[NSPipe alloc] init];//instead of [NSPipe pipe]
[tskLdapTask setStandardOutput: pipeLdapTask];//hope to get the tasks output in this file/pipe
//The magic line that keeps your log where it belongs, has to do with NSLog (see https://stackoverflow.com/questions/412562/execute-a-terminal-command-from-a-cocoa-app and here http://www.cocoadev.com/index.pl?NSTask )
[tskLdapTask setStandardInput:[NSPipe pipe]];
//fhLdapTask = [[NSFileHandle alloc] init];//would be redundand here, next line seems to do the trick also
fhLdapTask = [pipeLdapTask fileHandleForReading];
mdLdapTask = [NSMutableData dataWithCapacity:512];//prepare capturing the pipe buffer which is flushed on read and can overflow, start with 512 Bytes but it is mutable, so grows dynamically later
[tskLdapTask setLaunchPath: sLdapQueryCommand];
[tskLdapTask setArguments: aLdapQueryArgs];
#ifdef bDoDebug
NSLog (@"sLdapQueryCommand: %@\n", sLdapQueryCommand);
NSLog (@"aLdapQueryArgs: %@\n", aLdapQueryArgs );
NSLog (@"tskLdapTask: %@\n", [tskLdapTask arguments]);
#endif
[tskLdapTask launch];
while ([tskLdapTask isRunning]) {
[mdLdapTask appendData: [fhLdapTask readDataToEndOfFile]];
}
[tskLdapTask waitUntilExit];//might be redundant here.
[mdLdapTask appendData: [fhLdapTask readDataToEndOfFile]];//add another read for safety after process/command stops
NSString* sLdapOutput = [[NSString alloc] initWithData: mdLdapTask encoding: NSUTF8StringEncoding];//convert output to something readable, as NSData and NSMutableData are mere byte buffers
#ifdef bDoDebug
NSLog(@"LdapQueryOutput: %@\n", sLdapOutput);
#endif
//Ok now we have the printservers from Active Directory, lets parse the output and show the list to the user in its combo box
//output is formatted as this, one printserver per line
//dn: CN=PSyourPrintServer,OU=Computers,DC=yourBaseDomainToSearchIn,DC=com
//so we have to search for "dn: CN=" to retrieve each printserver's name
//unfortunately splitting this up will give us a first line containing only "" empty string, which we can replace with the word "choose"
//appearing as first entry in the comboBox
aPrintServers = (NSMutableArray*)[sLdapOutput componentsSeparatedByString:@"dn: CN="];//split output into single lines and store it in the NSMutableArray aPrintServers
#ifdef bDoDebug
NSLog(@"aPrintServers: %@\n", aPrintServers);
#endif
if ([[aPrintServers objectAtIndex: 0 ] compare: @"" options: NSLiteralSearch] == NSOrderedSame){
[aPrintServers replaceObjectAtIndex: 0 withObject: slChoose];//replace with localized string "choose"
#ifdef bDoDebug
NSLog(@"aPrintServers: %@\n", aPrintServers);
#endif
}
//Now comes the tedious part to extract only the print-server-names from the single lines
NSRange r;
NSString* sTemp;
for (int i = 1; i < [aPrintServers count]; i++) {//skip first line with "choose". To get rid of the rest of the line, we must isolate/preserve the print server's name to the delimiting comma and remove all the remaining characters
sTemp = [aPrintServers objectAtIndex: i];
sTemp = [sTemp stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];//remove newlines and line feeds
#ifdef bDoDebug
NSLog(@"sTemp: %@\n", sTemp);
#endif
r = [sTemp rangeOfString: @","];//now find first comma to remove the whole rest of the line
//r.length = [sTemp lengthOfBytesUsingEncoding:NSUTF8StringEncoding];
r.length = [sTemp length] - r.location;//calculate number of chars between first comma found and lenght of string
#ifdef bDoDebug
NSLog(@"range: %i, %i\n", r.location, r.length);
#endif
sTemp = [sTemp stringByReplacingCharactersInRange:r withString: @"" ];//remove rest of line
#ifdef bDoDebug
NSLog(@"sTemp after replace: %@\n", sTemp);
#endif
[aPrintServers replaceObjectAtIndex: i withObject: sTemp];//put back string into array for display in comboBox
#ifdef bDoDebug
NSLog(@"aPrintServer: %@\n", [aPrintServers objectAtIndex: i]);
#endif
}
[comboPrintServer removeAllItems];//reset combo box
[comboPrintServer addItemsWithObjectValues:aPrintServers];
[comboPrintServer setNumberOfVisibleItems:aPrintServers.count];
[comboPrintServer selectItemAtIndex:0];
#ifdef bDoDebug
NSLog(@"comboPrintServer reloaded with new values.");
#endif
//release memory we used for LdapTask
[sLdapQueryCommand release];
[aLdapQueryArgs release];
[sLdapOutput release];
[fhLdapTask release];
[pipeLdapTask release];
// [tskLdapTask release];//strangely can not be explicitely released, might be autorelease anyway
// [mdLdapTask release];//strangely can not be explicitely released, might be autorelease anyway
[sTemp release];
}
}
于 2013-05-01T15:33:16.150 回答
0
我自己遇到过这样的例子，其中仅按组件分隔字符串是不够的，许多任务，例如
1）将令牌分类为类型
2）添加新令牌
3）在自定义闭包之间分隔字符串，如“{”和“} 之间的所有单词“
对于任何此类要求，我发现Parse Kit是救生员。
我用它成功地解析了 .PGN（prtable 游戏符号）文件，它非常快速且精简。
于 2014-01-15T12:45:48.403 回答