How to set TableStyle into Table

Hi,

  Now I want to create a table with w:tblStyle to replace a paragraph, and the value of the w:tblStyle is from the w:pStyle of the paragraph which is replaced. But it didn't work. The next lines is code.

 tblPr = new TableProperties();               

 tbl.AppendChild(tblPr);

  TableBorders tblBorders = new TableBorders();         

  tblPr.TableBorders = tblBorders; 

 TopBorder top = new TopBorder();         

  top.Color = "auto";         

  top.Size = 4;         

  top.Space = 0;         

  top.Val = BorderValues.Single;         

  tblBorders.AppendChild(top);

  ParagraphStyleId pStyle = p.Descendants<ParagraphStyleId>().FirstOrDefault(); // p is the replaced paragraph          

 if (null != pStyle && null != pStyle.Val)           

{               

  string pStyleVal = pStyle.Val.Value;
  TableStyle tblStyle = new TableStyle();               

  tblStyle.Val = pStyleVal;             

  tblPr.TableStyle = tblStyle;           

}

body.ReplaceChild(tbl, p);

There is a weird thing.The tblPr.TableStyle is not null after execute,but there is no w:tblStyle tag in the document. Give me a hand please!Thanks!!