我需要从字符串的末尾删除空格。我该怎么做呢? 示例:如果字符串是“Hello”,它必须变成“Hello”
当前回答
NSString *trimmedString = [string stringByTrimmingCharactersInSet:
[NSCharacterSet whitespaceAndNewlineCharacterSet]];
//for remove whitespace and new line character
NSString *trimmedString = [string stringByTrimmingCharactersInSet:
[NSCharacterSet punctuationCharacterSet]];
//for remove characters in punctuation category
还有许多其他字符集。根据你的要求自己检查一下。
其他回答
这将只删除您选择的尾随字符。
func trimRight(theString: String, charSet: NSCharacterSet) -> String {
var newString = theString
while String(newString.characters.last).rangeOfCharacterFromSet(charSet) != nil {
newString = String(newString.characters.dropLast())
}
return newString
}
从这里的答案来看:https://stackoverflow.com/a/5691567/251012
- (NSString *)stringByTrimmingTrailingCharactersInSet:(NSCharacterSet *)characterSet {
NSRange rangeOfLastWantedCharacter = [self rangeOfCharacterFromSet:[characterSet invertedSet]
options:NSBackwardsSearch];
if (rangeOfLastWantedCharacter.location == NSNotFound) {
return @"";
}
return [self substringToIndex:rangeOfLastWantedCharacter.location+1]; // non-inclusive
}
斯威夫特版本
只修整字符串末尾的空格:
private func removingSpacesAtTheEndOfAString(var str: String) -> String {
var i: Int = countElements(str) - 1, j: Int = i
while(i >= 0 && str[advance(str.startIndex, i)] == " ") {
--i
}
return str.substringWithRange(Range<String.Index>(start: str.startIndex, end: advance(str.endIndex, -(j - i))))
}
修整字符串两侧的空格:
var str: String = " Yolo "
var trimmedStr: String = str.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceCharacterSet())
另一个解决方案涉及创建可变字符串:
//make mutable string
NSMutableString *stringToTrim = [@" i needz trim " mutableCopy];
//pass it by reference to CFStringTrimSpace
CFStringTrimWhiteSpace((__bridge CFMutableStringRef) stringToTrim);
//stringToTrim is now "i needz trim"
在Swift中删除字符串开头和结尾的空格:
斯威夫特3
string.trimmingCharacters(in: .whitespacesAndNewlines)
Swift以前的版本
string.stringByTrimmingCharactersInSet(.whitespaceAndNewlineCharacterSet()))