using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.OleDb;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace ExcelWord
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }


        public DataSet getData()

        {

            //打开文件

            OpenFileDialog file = new OpenFileDialog();

            //file.Filter = "Excel(*.xlsx)|*.xlsx|Excel(*.xls)|*.xls";
            file.Filter = "Excel文件 |*.xlsx;*.xls";
            file.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);

            file.Multiselect = false;

            if (file.ShowDialog() == DialogResult.Cancel)

                return null;

            //判断文件后缀

            var path = file.FileName;

            string fileSuffix = System.IO.Path.GetExtension(path);

            if (string.IsNullOrEmpty(fileSuffix))

                return null;

            using (DataSet ds = new DataSet())

            {

                //判断Excel文件是2003版本还是2007版本

                string connString = "";

                if (fileSuffix == ".xls")

                    connString = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + path + ";" + ";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";

                else

                    connString = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + path + ";" + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1\"";

                //读取文件

                string sql_select = " SELECT * FROM [Sheet1$]";

                using (OleDbConnection conn = new OleDbConnection(connString))

                using (OleDbDataAdapter cmd = new OleDbDataAdapter(sql_select, conn))

                {

                    conn.Open();

                    cmd.Fill(ds);

                }

                if (ds == null || ds.Tables.Count <= 0) return null;

                return ds;

            }

        }

        private void button2_Click(object sender, EventArgs e)
        {
            dataGridView2.DataSource = null; //每次打开清空内容

            DataSet dataSet = getData();
            if (dataSet != null)
            {
                DataTable dt = dataSet.Tables[0];
                RemoveEmpty(dt);
                dataGridView2.DataSource = dt;
            }
        }

        //删除空行
        protected void RemoveEmpty(DataTable dt)
        {
            List<DataRow> removelist = new List<DataRow>();
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                bool IsNull = true;
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    if (!string.IsNullOrEmpty(dt.Rows[i][j].ToString().Trim()))
                    {
                        IsNull = false;
                    }
                }
                if (IsNull)
                {
                    removelist.Add(dt.Rows[i]);
                }
            }
            for (int i = 0; i < removelist.Count; i++)
            {
                dt.Rows.Remove(removelist[i]);
            }
        }

    }
}

c#：winform读取excel，并显示在griddataview_griddataview