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

解决方案在这里描述:如何从NSString的右端删除空白?

添加以下类别到NSString:

- (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
}

- (NSString *)stringByTrimmingTrailingWhitespaceAndNewlineCharacters {
    return [self stringByTrimmingTrailingCharactersInSet:
            [NSCharacterSet whitespaceAndNewlineCharacterSet]];
}

你可以这样使用它:

[yourNSString stringByTrimmingTrailingWhitespaceAndNewlineCharacters]

其他回答

给你…

- (NSString *)removeEndSpaceFrom:(NSString *)strtoremove{
    NSUInteger location = 0;
    unichar charBuffer[[strtoremove length]];
    [strtoremove getCharacters:charBuffer];
    int i = 0;
    for(i = [strtoremove length]; i >0; i--) {
        NSCharacterSet* charSet = [NSCharacterSet whitespaceCharacterSet];
        if(![charSet characterIsMember:charBuffer[i - 1]]) {
            break;
        }
    }
    return [strtoremove substringWithRange:NSMakeRange(location, i  - location)];
}

现在就叫它。假设你有一个字符串,它前面有空格,后面也有空格,你只想去掉末尾的空格,你可以这样调用它:

NSString *oneTwoThree = @"  TestString   ";
NSString *resultString;
resultString = [self removeEndSpaceFrom:oneTwoThree];

resultString的结尾将没有空格。

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()))

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())

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
}