过滤和排序swift数组

我有一个我要过滤的swift数组，这里是数组

let array = [apple,workshops,shopping,sports,parties,pantry,pen] 

我想过滤数组，使得以搜索字符串开头的项目出现在仅包含搜索字符串的项目之前

因此，当我搜索示例p时，结果应该是某种方式

 let array = [parties,pantry,pen,apple,workshops,shopping,sports] 

我试过这个

 tagSearchResults = tagSearchResults.filter({ (interestTag:InterestTag) -> Bool in let tmp: NSString = interestTag.tag let range = tmp.rangeOfString(searchText, options: NSStringCompareOptions.CaseInsensitiveSearch) return range.location != NSNotFound }) 

但这给了我包含搜索字符串的所有字符串。

那么伙计我怎么能这样做

Answer 1

你可以写

  let result = words .filter { $0.contains(keyword) } .sorted { ($0.hasPrefix(keyword) ? 0 : 1) < ($1.hasPrefix(keyword) ? 0 : 1) } 

例

 let words = ["apple", "workshops", "shopping", "sports", "parties", "pantry", "pen", "cat", "house"] let keyword = "p" let result = words .filter { $0.contains(keyword) } .sorted { ($0.hasPrefix(keyword) ? 0 : 1) < ($1.hasPrefix(keyword) ? 0 : 1) } // ["pen", "pantry", "parties", "apple", "workshops", "shopping", "sports"] 

Answer 2

尝试这个。 首先，它过滤数组以删除那些不包含搜索字符串的元素，然后使用自定义排序来优先选择以搜索字符串开头的项目。 通常，使用笛卡尔方法将问题分解为较小的子问题，而不是尝试一步解决问题。

 let searchString = "p" let array = ["apple", "workshops", "shopping", "sports", "parties", "pantry", "pen", "xyzzy"] let filteredArray = array.filter({ $0.contains(searchString) }) filteredArray // drops xyzzy let sortedArray = filteredArray.sorted(isOrderedBefore: { switch ($0.hasPrefix(searchString), $1.hasPrefix(searchString)) { case (true, true): return $0 < $1 case (true, false): return true case (false, true): return false case (false, false): return $0 < $1 } }) sortedArray // "pantry", "parties", "pen", "apple", "shopping", "sports", "workshops"] as required 

Answer 3

其他方式：

 let searchString = "p" let array = ["apple", "workshops", "shopping", "sports", "parties", "pantry", "pen", "xyzzy"] let result = array.filter{$0.containsString(searchString)} .map{($0.hasPrefix(searchString) ? 0 : 1, $0)} .sort{$0 < $1} .map{$1} print(result) //->["pantry", "parties", "pen", "apple", "shopping", "sports", "workshops"] 

（我不知道为什么，但我的Xcode花了很多时间来编译这些行。相信这个编译并最终按预期运行。）