使用数组

String.Join(System.Environment.NewLine, text.Split(System.Environment.NewLine.ToCharArray(), StringSplitOptions.RemoveEmptyEntries))

或正则表达式

or regular expression

System.Text.RegularExpressions.Regex.Replace(System.text, "[\\r\\n]+", System.Environment.NewLine, System.Text.RegularExpressions.RegexOptions.Multiline)

或最后循环

or loop at last

while (txt.Contains(System.Environment.NewLine + System.Environment.NewLine)) {
	txt = txt.Replace(System.Environment.NewLine + System.Environment.NewLine, System.Environment.NewLine);
}

获得Regex的帮助.下面的代码为我工作:

Take help of Regex. Below code worked for me:

textBox1.Text = Regex.Replace(textBox1.Text, "[\r\n]+", "\r\n");

希望这也对您有用.

Hope this works for you as well.