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Objective c “我该如何修剪?”&引用;及\";在NSMutableString中_Objective C_Nsmutablestring - Fatal编程技术网

Objective c “我该如何修剪?”&引用;及\";在NSMutableString中

Objective c “我该如何修剪?”&引用;及\";在NSMutableString中,objective-c,nsmutablestring,Objective C,Nsmutablestring,如何修剪NSMutableString中的“”和“\n”?调用ReplaceCurrencesofString:withString:options:range两次,然后将“”和“\n”替换为零?我知道这是一个老问题,但是可以修剪可变字符串,而无需返回新字符串。您只需要一个正则表达式,下面是一个示例: NSCharacterSet* charsToTrim = [NSCharacterSet characterSetWithCharactersInString:@" \n"]; NSString

如何修剪NSMutableString中的“”和“\n”?

调用ReplaceCurrencesofString:withString:options:range两次,然后将“”和“\n”替换为零?

我知道这是一个老问题,但是可以修剪可变字符串,而无需返回新字符串。您只需要一个正则表达式,下面是一个示例:

NSCharacterSet* charsToTrim = [NSCharacterSet characterSetWithCharactersInString:@" \n"];
NSString* trimmedStr = [aStr stringByTrimmingCharactersInSet:charsToTrim];
NSMutableString *mutable = [NSMutableString stringWithString:@" String to trim    \n"];

NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"\\n|  | $|^ " options:0 error:nil];
[regex replaceMatchesInString:mutable options:0 range:NSMakeRange(0, [mutable length]) withTemplate:@""];

这是一个好办法。它返回一个不可变的字符串,但实际上没有一个好的选择。另外,请查看并归档ER:Need for-[NSMutableString trimCharactersInSet:]的副本,这将起作用,但除非指定范围,否则它的效率将低于人们所希望的,因为它将在整个字符串中搜索这些字符(两次),而不仅仅是结尾,直到删除所有此类字符。它也不能很好地扩展到N个字符-这就是为什么我们有NSCharacterSet.:-)
NSMutableString *mutable = [NSMutableString stringWithString:@" String to trim    \n"];

NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"\\n|  | $|^ " options:0 error:nil];
[regex replaceMatchesInString:mutable options:0 range:NSMakeRange(0, [mutable length]) withTemplate:@""];