String usage in C ＃

1.string.join

In the specified String The specified separator is concatenated between each element of the array String, This produces a single concatenated string . for example ：

string [] array={
    abc,def,ghi};
string a = string.Join("-", array);

here a=“abc-def-ghi”;

2.string.IsNullOrWhiteSpace

Judge all blank characters , Function equivalent to string.IsNullOrEmpty and str.Trim().Length The sum of the , He gave the string to Char.IsWhiteSpace by ture Any character of will be correct . according to MSDN Explanation , This method will be more efficient and concise than calling the above two methods , So when judging this function , Recommended .