How to open existing word document through c#

This example shows how to open an existing word document in c# programming language.
Add reference of ‘Microsoft.Office.Interop.Word’ in your project.
This code example requires a document named Test.docx must exist in a D: drive.

        private void OpenWordDocument()
        {
            object objMissing = System.Reflection.Missing.Value;
            Microsoft.Office.Interop.Word._Application objWord;
            Microsoft.Office.Interop.Word._Document objDoc;
            objWord = new Microsoft.Office.Interop.Word.Application();
            object fileName = @"D:\Test.docx";
            objDoc=objWord.Documents.Open(ref fileName,
                ref objMissing, ref objMissing, ref objMissing, ref objMissing, ref objMissing,
                ref objMissing, ref objMissing, ref objMissing, ref objMissing, ref objMissing,
                ref objMissing, ref objMissing, ref objMissing, ref objMissing, ref objMissing);           
        }