String怎么转Date，在转String

如： 20130301 减去 1 怎么得到20130228

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如果你确定锋销是yyyyMMdd这个格式的！就这么写！
var dt = DateTime.ParseExact("20130301", "yyyyMMdd"袜梁, null);
dt.AddDays(-1);
string result = dt.ToString("yyyyMMdd"银好游);

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DateTime a = Convert.ToDateTime(Regex.Replace("20130301", @"档圆^(\d{4})(\d{2})(\并蠢滑d{2})$"绝腊, "$1-$2-$3", RegexOptions.IgnoreCase));

DateTime b = a.AddDays(-1);

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DateTime date = new DateTime();
date = Convert.ToDateTime("毁颤带和2013-03-01"纤行败);

string str =date.ToShortDateString();

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