在我的应用程序中,我想从字符串中删除除a-z字符以外的数字。如何只获取字符?
这是一个简短的答案,不需要任何冗长的编码
NSString *newString = [[tempstr componentsSeparatedByCharactersInSet:
[[NSCharacterSet letterCharacterSet] invertedSet]] componentsJoinedByString:@""];`
Swift 3:
(tempstr.components(separatedBy:NSCharacterSet.letters.inverted)).joined(separator: "")
例如:
("abc123".components(separatedBy:NSCharacterSet.letters.inverted)).joined(separator: "")
NSString *stringToFilter = @"filter-me";
NSMutableString *targetString = [NSMutableString string];
//set of characters which are required in the string......
NSCharacterSet *okCharacterSet = [NSCharacterSet characterSetWithCharactersInString:@"abcdefghijklmnopqrstuvwxyz"];
for(int i = 0; i < [stringToFilter length]; i++)
{
unichar currentChar = [stringToFilter characterAtIndex:i];
if([okCharacterSet characterIsMember:currentChar])
{
[targetString appendFormat:@"%C", currentChar];
}
}
NSLog(targetString);
[super viewDidLoad];
}
这是一个给我的答案,而且可以正常工作
NSString *originalString = @"(123) 123123 abc";
NSLog(@"%@", originalString);
NSMutableString *strippedString = [NSMutableString
stringWithCapacity:originalString.length];
NSScanner *scanner = [NSScanner scannerWithString:originalString];
NSCharacterSet *numbers = [NSCharacterSet
characterSetWithCharactersInString:@"abcdefghijklmnopqrstuvwxyz"];
while ([scanner isAtEnd] == NO) {
NSString *buffer;
if ([scanner scanCharactersFromSet:numbers intoString:&buffer]) {
[strippedString appendString:buffer];
} else {
[scanner setScanLocation:([scanner scanLocation] + 1)];
}
}
NSLog(@"%@", strippedString);