元哥的筆記

C# 6 多了FormattableString，這部分目前理解的部分有大兩大塊
1.針對文化產生結果的字串
2.可以進行做後續的參數化

來看第一個Sample來佐證

            //依據文化特定字串來實作FormattableString
            var cultures = new System.Globalization.CultureInfo[]
            {
                System.Globalization.CultureInfo.GetCultureInfo("en-US"),
                System.Globalization.CultureInfo.GetCultureInfo("en-GB"),
                System.Globalization.CultureInfo.GetCultureInfo("nl-NL"),
                System.Globalization.CultureInfo.InvariantCulture
            };

            var date = DateTime.Now;
            var number = 31_415_926.536;
            FormattableString message = $"{date,20}{number,20:N3}";
            foreach (var culture in cultures)
            {
                var cultureSpecificMessage = message.ToString(culture);
                Console.WriteLine($"{culture.Name,-10}{cultureSpecificMessage}");
            }

第二個例子，針對這樣特性可以進行參數化動作

            //某些狀況可以參數化
            var name = "Eddie";
            FormattableString fmtString = $"hello {name}";
            Console.WriteLine(fmtString.ArgumentCount);  //1
            Console.WriteLine(fmtString.Format);  //hello {0}
            foreach (var arg in fmtString.GetArguments())
            {
                Console.WriteLine(arg);  //Eddie
                Console.WriteLine(arg.GetType()); //System.String
            }
            

元哥的筆記