string myString = "This is a string that will be splitted by this and that";
string foo = myString.ToUpper();
string[] byThis = foo.Split(new string[] { "THIS" }, StringSplitOptions.RemoveEmptyEntries);
string[] byThat = foo.Split(new string[] { "THAT" }, StringSplitOptions.RemoveEmptyEntries);
string[] all = foo.Split(new string[] { "THAT", "THIS" }, StringSplitOptions.RemoveEmptyEntries);
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或者你可以使用正则表达式
string[] all = System.Text.RegularExpressions.Regex.Split(myString, "your pattern", System.Text.RegularExpressions.RegexOptions.IgnoreCase);
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