从字符串中删除空格和多行？
我有一个字符串，像这样：
" \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n " 我想结果是：
"assddd\nadjffffdd\ntjhfhdf".
1：我使用trimmingCharacters来删除开头和结尾：
let title = " \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n".trimmingCharacters(in: .whitespacesAndNewlines)
2：删除空格
let result = title.replacingOccurrences(of: " ", with: "")
但是，如何在角色之间保留第一个“\ n”并删除其他“\ n”？
您可以使用正则表达式找到两个或多个连续的换行符，并用一个换行符替换它们。 例：
let s1 = "AA\n\nBB\nCC\n\n\n\n\nDD" let s2 = s1.replacingOccurrences(of: "\\n{2,}", with: "\n", options: .regularExpression) print(s1.debugDescription) // "AA\n\nBB\nCC\n\n\n\n\nDD" print(s2.debugDescription) // "AA\nBB\nCC\nDD"
适用于您的案例：
let title = " \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n " let result = title.trimmingCharacters(in: .whitespacesAndNewlines) .replacingOccurrences(of: " ", with: "") .replacingOccurrences(of: "\\n{2,}", with: "\n", options: .regularExpression) print(result.debugDescription) // "assddd\nadjffffdd\ntjhfhdf"
可能的解决方案：
let str = " \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n " print("str: \(str)") let str2 = str.replacingOccurrences(of: " ", with: "") print("str2: \(str2)") let lines = str2.components(separatedBy:"\n") print("lines: \(lines)") let linesFiltered = lines.filter({($0.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)).count > 0}) print("linesFiltered: \(linesFiltered)") let linesTrimmed = linesFiltered.map({$0.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)}) print("linesTrimmed: \(linesTrimmed)") let endStr = linesTrimmed.joined(separator: "\n") print("endStr:\n\(endStr)") print("endStr:\n\(endStr.debugDescription)")
想法：
删除所有空格，因为您不需要它们。
获取由breakLine（“\ n”）分隔的所有行
因为如果重复需要重新组装它们，并将它们放在一个数组中
删除空行（只有空格和/或新行）
删除每行前后的空格/换行符（修剪）
重新组合字符串
这个输出：
str: assddd adjf fff dd tjhfhdf str2: assddd adjffffdd tjhfhdf lines: ["", "assddd", "", "", "", "", "adjffffdd", "", "", "", "tjhfhdf", ""] linesFiltered: ["assddd", "adjffffdd", "tjhfhdf"] linesTrimmed: ["assddd", "adjffffdd", "tjhfhdf"] endStr: assddd adjffffdd tjhfhdf endStr: "assddd\nadjffffdd\ntjhfhdf"
正如我在使用常规表达的评论中所说，你可以这样做，
func stringByAdjustingString(text:String) ->String{ do{ let regex = try NSRegularExpression(pattern: "\\n+", options:[.dotMatchesLineSeparators]) let resultString = regex.stringByReplacingMatches(in: text, range: NSMakeRange(0, text.utf16.count), withTemplate: "\n") return resultString.replacingOccurrences(of: " ", with: "").trimmingCharacters(in: .whitespacesAndNewlines) } catch{ return "" } }
输入： “\ n assddd \ n \ n \ n \ n \ n adjf fff dd \ n \ n \ n \ n tjhfhdf \ n”
输出： “assddd \ nadjffffdd \ ntjhfhdf”
It should help you var str = " \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n " str = str.trimmingCharacters(in: .whitespacesAndNewlines) str = str.replacingOccurrences(of: " ", with: "") //str = str.replacingOccurrences(of: "\n\n", with: "\n") let array = str.components(separatedBy: "\n") var finalArray = [String]() for x in array { if !x.isEmpty { finalArray.append(x) } } str = finalArray.joined(separator: "\n")
从您的示例文本开始，我们可以修改结尾：
let sample = " \n assddd\n\n\n\n\n adjf fff dd \n\n\n\n tjhfhdf \n " let trimmedEnds = sample.trimmingCharacters(in: .whitespacesAndNewlines)
如果您只想删除空格并压缩换行符：
let noHorizSpace = trimmedEnds.replacingOccurrences(of: " ", with: "") // remove all spaces let singleVertSpace = noHorizSpace.replacingOccurrences(of: "\\n{2,}", with: "\n", options: .regularExpression) // squash runs of two or more newlines
或者使用空格的正则表达式：
let noHorizSpace = trimmedEnds.replacingOccurrences(of: " +", with: "", options: .regularExpression) let singleVertSpace = noHorizSpace.replacingOccurrences(of: "\\n{2,}", with: "\n", options: .regularExpression)
但是（为了好玩？）所有Unicode水平（空格，制表符等）和垂直（换行符，换页符，段落分隔符等）怎么样？ 为此，有RE模式\h和\v ：
let noHorizSpace = trimmedEnds.replacingOccurrences(of: "\\h+", with: "", options: .regularExpression) let singleVertSpace = noHorizSpace.replacingOccurrences(of: "\\v+", with: "\n", options: .regularExpression)
您可以使用单个正则表达式解决此问题，但最好注意ICU RE用户指南中的建议并使用多个更简单的RE。
您可以使用以下方法删除字符串中的空格
yourString.trimmingCharacters(in: .whitespaces)
或者如果你想要删除白色空格和线条
yourString.trimmingCharacters(in: .whitespacesAndNewlines)
我希望它能有所帮助！