System.Text.RegularExpressions.Match m = System.Text.RegularExpressions.Regex.Match("bbbbb<Abc:if({Abc:data_19_新闻图片}!=\"\")><div class=\"newsUl-list-r\"><img src=\"{Abc:data_19_新闻图片}\" /></div><Abc:else>ddddd<Abc:endif>aaaaa", @"<Abc:if([.\w\W]*?)<Abc:endif>"); var value = m.Groups[1].Value;
string text = @"bbbbb<Abc:if({Abc:data_19_新闻图片}!="")><div class=""newsUl-list-r""><img src=""{Abc:data_19_新闻图片}"" /></div><Abc:else>ddddd<Abc:endif>aaaaa"; string result = Regex.Match(text, @"(?i)<abc:if[\s\S]*?<Abc:endif>").Value;
var value = m.Groups[1].Value;
string result = Regex.Match(text, @"(?i)<abc:if[\s\S]*?<Abc:endif>").Value;