求高手将这段VB代码翻译成C#
public string jiemi(string PlainStr, string key)
{
     string str3;
     int start = 1;
     if ((Strings.Len(PlainStr) % 2) == 0)
     {
         string str4 = Strings.StrReverse(Strings.Left(PlainStr, (int) Math.Round
((double) (((double) Strings.Len(PlainStr)) / 2.0))));
         string str5 = Strings.StrReverse(Strings.Right(PlainStr, (int) Math.Round
((double) (((double) Strings.Len(PlainStr)) / 2.0))));
         PlainStr = str4 + str5;
     }
     int num3 = Strings.Len(PlainStr);
     for (int i = 1; i <= num3; i++)
     {
         string str6 = Strings.Mid(PlainStr, i, 1);
         string str2 = Strings.Mid(key, start, 1);
         if (((((Strings.Asc(str6) ^ Strings.Asc(str2)) < 0x20) | ((Strings.Asc(str6)  
^ Strings.Asc(str2)) > 0x7e)) | (Strings.Asc(str6) < 0)) | (Strings.Asc(str6) >  
0xff))
         {
             str3 = str3 + str6;
         }
         else
         {
             str3 = str3 + StringType.FromChar(Strings.Chr(Strings.Asc(str6) ^  
Strings.Asc(str2)));
         }
         if (start == Strings.Len(key))
         {
             start = 0;
         }
         start++;
     }
     return str3;
}    
------解决方案--------------------这个就是C#代码呀,Microsoft.VisualBasic名称空间下的,楼主自己照着msdn转吧,很容易的
------解决方案--------------------VB是这样的
  Function jiemi(ByVal PlainStr As String,ByVal keyAs String) As String
     Dim str3 As String   --声明变量
     Dim start As Int32
   If pDayCount >= 3 Then  --if 判定
       lResult = True
   End If
For Each lEmployeeStartDateDataRow In lDataSet.Tables("EmployeeStartDateTable").Rows
.....
Next    ---for 循环