https://blog.csdn.net/u010082526/article/details/51733705?utm_source=blogxgwz4&utm_medium=distribute.pc_relevant_bbs_down.none-task-blog-baidujs-2.nonecase&depth_1-utm_source=distribute.pc_relevant_bbs_down.none-task-blog-baidujs-2.nonecase

1、C#裡的SubString

String.SubString(int index,int length)

index:開始位置，從0開始

length:你要取的子字串的長度

獲取字元，然後擷取拼接

2、C#語言之“string格式的日期時間字串轉為DateTime型別”的方法

方法一：Convert.ToDateTime(string)

string格式有要求，必須是yyyy-MM-dd hh:mm:ss

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方法二：Convert.ToDateTime(string, IFormatProvider)

DateTime dt;

DateTimeFormatInfo dtFormat = new System.GlobalizationDateTimeFormatInfo();

dtFormat.ShortDatePattern = "yyyy/MM/dd";

dt = Convert.ToDateTime("2011/05/26", dtFormat);

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方法二：DateTime.ParseExact()

string dateString = "20110526";

DateTime dt = DateTime.ParseExact(dateString, "yyyyMMdd",System.Globalization.CultureInfo.CurrentCulture);

或者

DateTime dt = DateTime.ParseExact(dateString, "yyyyMMdd",System.Globalization.CultureInfo.InvariantCulture);

附參考資訊：

CultureInfo cultureInfo = CultureInfo.CreateSpecificCulture("en-US");
string format = "ddd MMM d HH:mm:ss zz00 yyyy";
string stringValue = DateTime.Now.ToString(format, cultureInfo); // 得到日期字串
DateTime datetime = DateTime.ParseExact("Wed Aug 25 16:28:03 +0800 2010", format, cultureInfo); // 將字串轉換成日期