如何使用 Swift 5 中结构的键和值过滤字典？

Question

如何过滤具有Swift 5 结构值的字典？ 我打算从池（字典）中过滤出结构字段'stock'等于'STOCK01'(A1, A2 and A3)的股票。

var pool = [String: StockOption]()

pool[ "A1" ] = StockOption( code: "A1", strikePrice: "10.1", stock: "STOCK01" )
pool[ "A2" ] = StockOption( code: "A2", strikePrice: "11.5", stock: "STOCK01" )
pool[ "A3" ] = StockOption( code: "A3", strikePrice: "12.7", stock: "STOCK01" )

pool[ "B5" ] = StockOption( code: "B5", strikePrice: "23.3", stock: "STOCK02" )
pool[ "B6" ] = StockOption( code: "B6", strikePrice: "24.3", stock: "STOCK02" )


struct StockOption {

    var code                  : String?       // "A1", "B2", ..., "ZE43", ... (unique key) ,
    var strikePrice           : String?       // just a price stored in string

    var stock                 : String?       // "STOCK01", "STOCK02", ... "STOCK99" (Can repeat)
}

Answer 1

你需要

let res = pool.filter { $0.value.stock == "STOCK01" }