C# 各种导入 Excel 文件的数据的方法总结

Posted 2020-09-19

在导入之前都需要将上传的文件保存到服务器，所以避免重复的写这些代码，先贴出上传文件并保存到服务器指定路径的代码。

protected void btnImport_Click(object sender, EventArgs e)
        {
            Random random = new Random();
            ImportClass Import = new ImportClass();

            //保存文件的虚拟路径
            string path = "Import/";

            //获取选择的文件名
            string fileName = FileUpload1.FileName;

            //获取文件扩展名称
            string fileExt = Path.GetExtension(fileName);

            //生成新文件名
            string newName = DateTime.Now.ToString("yyyyMMddHHmmssfff") + random.Next(0, 9999).ToString();

            //获取指定虚机路径的物理路径
            string fullPath = HttpContext.Current.Server.MapPath(path);

            //上传文件保存路径
            string savePath = fullPath + newName + fileExt;

            //保存文件到服务器
            FileUpload1.SaveAs(savePath);

            try
            {
                //获取导入的数据
                DataSet ds = Import.ImportExcel(savePath);
                if (ds != null && ds.Tables.Count > 0)
                {
                    //这里可以写插入数据库的方法
                }
            }
            catch (Exception ex)
            {

                throw;
            }
        }

View Code

第一种：OleDB

public DataSet ImportExcel(string filePath)
        {
            DataSet ds = null;
            OleDbConnection conn;

            string strConn = string.Empty;
            string sheetName = string.Empty;

            try
            {
                // Excel 2003 版本连接字符串
                strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filePath + ";Extended Properties=‘Excel 8.0; HDR=YES; IMEX=1;‘";
                conn = new OleDbConnection(strConn);
                conn.Open();
            }
            catch
            {
                // Excel 2007 以上版本连接字符串
                strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + filePath + ";Extended Properties=‘Excel 12.0;HDR=Yes;IMEX=1;‘";
                conn = new OleDbConnection(strConn);
                conn.Open();
            }

            //获取所有的 sheet 表
            DataTable dtSheetName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "Table" });

            ds = new DataSet();

            for (int i = 0; i < dtSheetName.Rows.Count; i++)
            {
                DataTable dt = new DataTable();
                dt.TableName = "table" + i.ToString();

                //获取表名
                sheetName = dtSheetName.Rows[i]["TABLE_NAME"].ToString();

                OleDbDataAdapter oleda = new OleDbDataAdapter("select * from [" + sheetName + "]", conn);

                oleda.Fill(dt);

                ds.Tables.Add(dt);
            }

            return ds;
        }

View Code

除了读取过程不太灵活之外，这种读取方式还有个弊端就是，当 Excel 数据量很大时。会非常占用内存，当内存不够时会抛出内存溢出的异常，不过一般都能适用了。

 

第二种：Microsoft.Office.Interop.Excel.dll

public DataSet ImportExcel(string filePath)
        {
            DataSet ds = null;
            DataTable dt = null;

            Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
            Microsoft.Office.Interop.Excel.Workbook workbook = null;
            Microsoft.Office.Interop.Excel.Worksheet worksheet = null;
            Microsoft.Office.Interop.Excel.Sheets sheets = null;
            Microsoft.Office.Interop.Excel.Range range = null;
            object missing = System.Reflection.Missing.Value;

            try
            {
                if (excel == null)
                {
                    return null;
                }

                //打开 Excel 文件
                workbook = excel.Workbooks.Open(filePath, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing);

                //获取所有的 sheet 表
                sheets = workbook.Worksheets;

                ds = new DataSet();

                for (int i = 1; i <= sheets.Count; i++)
                {
                    //获取第一个表
                    worksheet = (Microsoft.Office.Interop.Excel.Worksheet)sheets.get_Item(i);

                    int rowCount = worksheet.UsedRange.Rows.Count;
                    int colCount = worksheet.UsedRange.Columns.Count;

                    int rowIndex = 1;   //起始行为 1
                    int colIndex = 1;   //起始列为 1

                    DataColumn dc;
                    dt = new DataTable();
                    dt.TableName = "table" + i.ToString();

                    //读取列名
                    for (int j = 0; j < colCount; j++)
                    {
                        range = worksheet.Cells[rowIndex, colIndex + j];

                        dc = new DataColumn();
                        dc.DataType = Type.GetType("System.String");
                        dc.ColumnName = range.Text.ToString().Trim();

                        //添加列
                        dt.Columns.Add(dc);
                    }

                    //读取行数据
                    for (int k = 1; k < rowCount; k++)
                    {
                        DataRow dr = dt.NewRow();
                        for (int l = 0; l < colCount; l++)
                        {
                            range = worksheet.Cells[rowIndex + k, colIndex + l];

                            //使用 range.Value.ToString(); 或 range.Value2.ToString(); 或 range.Text.ToString(); 都可以获取单元格的值
                            dr[l] = range.Text.ToString();
                        }
                        dt.Rows.Add(dr.ItemArray);
                    }

                    ds.Tables.Add(dt);
                }
            }
            catch (Exception ex)
            {

                throw;
            }

            return ds;
        }

View Code

这种方法首先需要安装有 office Excel，并且是一个单元格一个单元格的读取，所以性能会比较差。

 

未完待续。。。