ALLCAPS value cant convert to other other cases , anyone have solution?

See more:

C#

regular-expression

in this coding I replace all roman letter terms to SMALLCAPS,CAPS CASE, LOWER CASE , the ALLCAPS value cant convert to other cases

public void OxidationNumbers(string scase)
      {
          if (_doc == null) return;
          else if (string.IsNullOrWhiteSpace(_doc.Content.Text)) return;
          Regex regex;
          MatchCollection mc;
          if (scase == "sc")
          {
              regex = new Regex(@"(?<roman>\b[IVXLCDM]+\b)|(?<roman>\b[ivxlcdm]+\b)");
              mc=regex.Matches(_doc.Content.Text);
           }
          else if (scase == "uc")
          {
              regex = new Regex(@"(?<roman>\b[ivxlcdm]+\b)");
              mc=regex.Matches(_doc.Content.Text);
          }
          else
             regex = new Regex(@"(?<roman>\b[IVXLCDM]+\b)");

          this.captureOxidation(_doc.Content, scase, regex);
          if (this._doc.Footnotes.Count > 0) this.captureOxidation(this._doc.StoryRanges[Word.WdStoryType.wdFootnotesStory], scase,regex);
          if (this._doc.Endnotes.Count > 0) this.captureOxidation(this._doc.StoryRanges[Word.WdStoryType.wdEndnotesStory], scase, regex);
      }

      public void captureOxidation(Word.Range range,string scase,Regex regex)
      {

          string message = "Do You Want Change This Occurance";
          string title = "Case Selection";
          MessageBoxButtons buttons = MessageBoxButtons.YesNo;
          Word.Range findRange = range.Duplicate;
          findRange.Collapse(Word.WdCollapseDirection.wdCollapseStart);

          foreach (Match match in regex.Matches(range.Text))
          {
              findRange.Find.MatchCase = true;
              findRange.Find.MatchWholeWord = true;
              findRange.Find.Text = match.Value;

              if (findRange.Find.Execute2007(Forward: true, Wrap: Word.WdFindWrap.wdFindContinue, Replace: Word.WdReplace.wdReplaceNone))
              {
                  if (!findRange.InRange(range)) return;
                  Word.Range temp = findRange.Duplicate;
                  temp.Select();
                  if (temp.Font.SmallCaps==-1 && scase=="sc"){}
                  else
                  {
                      DialogResult result = MessageBox.Show(message, title, buttons, MessageBoxIcon.Question);
                      if (result == DialogResult.Yes)
                      {
                          switch (scase)
                          {
                              case "sc":

                                  temp.Case = Word.WdCharacterCase.wdLowerCase;
                                  temp.Font.SmallCaps = 1;
                                  temp.Font.AllCaps = 0;
                                  break;

                              case "uc":
                                  temp.Case = Word.WdCharacterCase.wdUpperCase;
                                  temp.Font.SmallCaps = 0;
                                  temp.Font.AllCaps = 0;
                                  break;

                              case "lc":
                                  temp.Case = Word.WdCharacterCase.wdLowerCase;
                                  temp.Font.SmallCaps = 0;
                                  temp.Font.AllCaps = 0;
                                  break;
                          }
                      }
                  }
                  findRange.Collapse(Word.WdCollapseDirection.wdCollapseEnd);
              }
          }
      }
  }

In this code I select the ALLCAPS value, when execute(change from ALLCAPS to other cases) find.execute2007() not accept the allcaps value any one give solution