C#多线程中，我们可以使用async和await来异步处理耗时任务。
现在我们打开一个Excel表格，将Excel表格的每一行数据进行处理，并存储到数据库中
新建Windows应用程序DataImportDemo，.net framework 4.6.1
将默认的Form1重命名为FormDataImport，
窗体FormDataImport设计如图：
窗体FormDataImport设计器代码如下：
FormDataImport.Designer.cs文件
namespace DataImportDemo
{
partial class FormDataImport
{
/// <summary>
/// 必需的设计器变量。
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
/// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows 窗体设计器生成的代码
/// <summary>
/// 设计器支持所需的方法 - 不要修改
/// 使用代码编辑器修改此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.dgvData = new System.Windows.Forms.DataGridView();
this.btnSave = new System.Windows.Forms.Button();
this.rtxtMessage = new System.Windows.Forms.RichTextBox();
this.btnExport = new System.Windows.Forms.Button();
this.dgvcCoreID = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.dgvcModuleBarcode = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.dgvcPoleCode = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.dgvcModuleCategory = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.progressBarImport = new System.Windows.Forms.ProgressBar();
((System.ComponentModel.ISupportInitialize)(this.dgvData)).BeginInit();
this.SuspendLayout();
//
// dgvData
//
this.dgvData.AllowUserToAddRows = false;
this.dgvData.AllowUserToDeleteRows = false;
this.dgvData.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
this.dgvData.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
this.dgvcCoreID,
this.dgvcModuleBarcode,
this.dgvcPoleCode,
this.dgvcModuleCategory});
this.dgvData.Location = new System.Drawing.Point(12, 61);
this.dgvData.Name = "dgvData";
this.dgvData.ReadOnly = true;
this.dgvData.RowTemplate.Height = 23;
this.dgvData.Size = new System.Drawing.Size(627, 628);
this.dgvData.TabIndex = 0;
//
// btnSave
//
this.btnSave.Font = new System.Drawing.Font("宋体", 16F);
this.btnSave.Location = new System.Drawing.Point(67, 9);
this.btnSave.Name = "btnSave";
this.btnSave.Size = new System.Drawing.Size(233, 43);
this.btnSave.TabIndex = 1;
this.btnSave.Text = "打开Excel并导入数据";
this.btnSave.UseVisualStyleBackColor = true;
this.btnSave.Click += new System.EventHandler(this.btnSave_Click);
//
// rtxtMessage
//
this.rtxtMessage.Location = new System.Drawing.Point(645, 61);
this.rtxtMessage.Name = "rtxtMessage";
this.rtxtMessage.Size = new System.Drawing.Size(621, 628);
this.rtxtMessage.TabIndex = 2;
this.rtxtMessage.Text = "";
//
// btnExport
//
this.btnExport.Font = new System.Drawing.Font("宋体", 16F);
this.btnExport.Location = new System.Drawing.Point(336, 9);
this.btnExport.Name = "btnExport";
this.btnExport.Size = new System.Drawing.Size(122, 43);
this.btnExport.TabIndex = 3;
this.btnExport.Text = "导出模板";
this.btnExport.UseVisualStyleBackColor = true;
this.btnExport.Click += new System.EventHandler(this.btnExport_Click);
//
// dgvcCoreID
//
this.dgvcCoreID.HeaderText = "序号";
this.dgvcCoreID.Name = "dgvcCoreID";
this.dgvcCoreID.ReadOnly = true;
//
// dgvcModuleBarcode
//
this.dgvcModuleBarcode.HeaderText = "模组条码";
this.dgvcModuleBarcode.Name = "dgvcModuleBarcode";
this.dgvcModuleBarcode.ReadOnly = true;
this.dgvcModuleBarcode.Width = 180;
//
// dgvcPoleCode
//
this.dgvcPoleCode.HeaderText = "极性编码";
this.dgvcPoleCode.Name = "dgvcPoleCode";
this.dgvcPoleCode.ReadOnly = true;
//
// dgvcModuleCategory
//
this.dgvcModuleCategory.HeaderText = "模组类型";
this.dgvcModuleCategory.Name = "dgvcModuleCategory";
this.dgvcModuleCategory.ReadOnly = true;
this.dgvcModuleCategory.Width = 140;
//
// progressBarImport
//
this.progressBarImport.Location = new System.Drawing.Point(529, 15);
this.progressBarImport.Name = "progressBarImport";
this.progressBarImport.Size = new System.Drawing.Size(737, 23);
this.progressBarImport.TabIndex = 4;
//
// FormDataImport
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(1305, 710);
this.Controls.Add(this.progressBarImport);
this.Controls.Add(this.btnExport);
this.Controls.Add(this.rtxtMessage);
this.Controls.Add(this.btnSave);
this.Controls.Add(this.dgvData);
this.Name = "FormDataImport";
this.Text = "数据导入使用async,await异步处理耗时任务";
((System.ComponentModel.ISupportInitialize)(this.dgvData)).EndInit();
this.ResumeLayout(false);
}
#endregion
private System.Windows.Forms.DataGridView dgvData;
private System.Windows.Forms.Button btnSave;
private System.Windows.Forms.RichTextBox rtxtMessage;
private System.Windows.Forms.Button btnExport;
private System.Windows.Forms.DataGridViewTextBoxColumn dgvcCoreID;
private System.Windows.Forms.DataGridViewTextBoxColumn dgvcModuleBarcode;
private System.Windows.Forms.DataGridViewTextBoxColumn dgvcPoleCode;
private System.Windows.Forms.DataGridViewTextBoxColumn dgvcModuleCategory;
private System.Windows.Forms.ProgressBar progressBarImport;
}
}
添加对NPOI框架的引用
添加对【NPOI.dll、NPOI.OOXML.dll、NPOI.OpenXml4Net.dll、NPOI.OpenXmlFormats.dll】类库的引用.
新建类NpoiExcelOperateUtil，用于【Excel表格与DataTable内存数据表的相互转换操作】
NpoiExcelOperateUtil.cs源程序：
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DataImportDemo
{
/// <summary>
/// Excel表格与DataTable内存数据表的相互转换操作类
/// 斯内科 2023-08-08
/// </summary>
public static class NpoiExcelOperateUtil
{
/// <summary>
/// Excel的第一个工作簿（Sheet）转化成DataTable
/// 使用EXCEL的第一个工作簿，默认为Sheet1
/// </summary>
/// <param name="file"></param>
/// <returns></returns>
public static DataTable ExcelToTable(string file)
{
DataTable dt = new DataTable();
IWorkbook workbook;
string fileExt = Path.GetExtension(file).ToLower();
using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
{
//XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
if (fileExt == ".xlsx")
{
workbook = new XSSFWorkbook(fs);
}
else if (fileExt == ".xls")
{
workbook = new HSSFWorkbook(fs);
}
else
{
return null;
}
//第一个工作簿
ISheet sheet = workbook.GetSheetAt(0);
if (sheet == null)
{
return null;
}
return ExcelToTable(file, sheet.SheetName);
}
}
/// <summary>
/// Excel的指定Sheet转化成内存表
/// </summary>
/// <param name="file">路径</param>
/// <param name="sheetName">sheet名称</param>
/// <returns></returns>
public static DataTable ExcelToTable(string file, string sheetName)
{
DataTable[] dataTables = ExcelToTable(file, new List<string>() { sheetName });
if (dataTables != null && dataTables.Length > 0)
{
return dataTables[0];
}
return null;
}
/// <summary>
/// 一个excel文件的多个Sheet转化成内存表数组，
/// 每个Sheet都对应一个数据表
/// </summary>
/// <param name="file">路径</param>
/// <param name="list_SheetName">sheet名称集合</param>
/// <returns></returns>
public static DataTable[] ExcelToTable(string file, List<string> list_SheetName)
{
int count = list_SheetName.Count;
DataTable[] dtS = new DataTable[count];
//===============================//
IWorkbook workbook;
string fileExt = Path.GetExtension(file).ToLower();
using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
{
//XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
if (fileExt == ".xlsx")
{
workbook = new XSSFWorkbook(fs);
}
else if (fileExt == ".xls")
{
workbook = new HSSFWorkbook(fs);
}
else
{
return null;
}
ISheet[] sheetS = new ISheet[count];
for (int k = 0; k < count; k++)
{
dtS[k] = new DataTable(list_SheetName[k]);
sheetS[k] = workbook.GetSheet(list_SheetName[k]);
ISheet sheet = sheetS[k];
if (sheet == null)
{
continue;
}
DataTable dt = new DataTable(list_SheetName[k]);
//表头
IRow header = sheet.GetRow(sheet.FirstRowNum);
List<int> columns = new List<int>();
for (int i = 0; i < header.LastCellNum; i++)
{
object obj = GetValueType(header.GetCell(i));
if (obj == null || obj.ToString() == string.Empty)
{
dt.Columns.Add(new DataColumn("Columns" + i.ToString()));
}
else
dt.Columns.Add(new DataColumn(obj.ToString()));
columns.Add(i);
}
//数据
for (int i = sheet.FirstRowNum + 1; i <= sheet.LastRowNum; i++)
{
DataRow dr = dt.NewRow();
bool hasValue = false;
foreach (int j in columns)
{
dr[j] = GetValueType(sheet.GetRow(i).GetCell(j));
if (dr[j] != null && dr[j].ToString() != string.Empty)
{
hasValue = true;
}
}
if (hasValue)
{
dt.Rows.Add(dr);
}
}
dtS[k] = dt;
}
}
return dtS;
}
/// <summary>
/// Datable导出成Excel
/// </summary>
/// <param name="dt"></param>
/// <param name="file"></param>
public static void TableToExcel(DataTable dt, string file)
{
IWorkbook workbook;
string fileExt = Path.GetExtension(file).ToLower();
if (fileExt == ".xlsx")
{
//workbook = new XSSFWorkbook();
workbook = new HSSFWorkbook();
}
else if (fileExt == ".xls")
{
workbook = new HSSFWorkbook();
}
else
{
workbook = null;
}
if (workbook == null)
{
return;
}
ISheet sheet = string.IsNullOrEmpty(dt.TableName) ? workbook.CreateSheet("Sheet1") : workbook.CreateSheet(dt.TableName);
//表头
IRow row = sheet.CreateRow(0);
for (int i = 0; i < dt.Columns.Count; i++)
{
ICell cell = row.CreateCell(i);
cell.SetCellValue(dt.Columns[i].ColumnName);
}
//数据
for (int i = 0; i < dt.Rows.Count; i++)
{
IRow row1 = sheet.CreateRow(i + 1);
for (int j = 0; j < dt.Columns.Count; j++)
{
ICell cell = row1.CreateCell(j);
cell.SetCellValue(dt.Rows[i][j].ToString());
}
}
//转为字节数组
MemoryStream stream = new MemoryStream();
workbook.Write(stream);
var buf = stream.ToArray();
//保存为Excel文件
using (FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write))
{
fs.Write(buf, 0, buf.Length);
fs.Flush();
}
}
/// <summary>
/// 获取单元格类型
/// </summary>
/// <param name="cell"></param>
/// <returns></returns>
private static object GetValueType(ICell cell)
{
if (cell == null)
return null;
switch (cell.CellType)
{
case CellType.Blank: //BLANK:
return null;
case CellType.Boolean: //BOOLEAN:
return cell.BooleanCellValue;
case CellType.Numeric: //NUMERIC:
return cell.NumericCellValue;
case CellType.String: //STRING:
return cell.StringCellValue;
case CellType.Error: //ERROR:
return cell.ErrorCellValue;
case CellType.Formula: //FORMULA:
default:
return "=" + cell.CellFormula;
}
}
}
}
窗体FormDataImport的异步耗时任务代码如下：
FormDataImport.cs文件
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace DataImportDemo
{
public partial class FormDataImport : Form
{
public FormDataImport()
{
InitializeComponent();
rtxtMessage.ReadOnly = true;
progressBarImport.Value = 0;
dgvData.AutoGenerateColumns = false;
dgvcCoreID.DataPropertyName = "序号";
dgvcModuleBarcode.DataPropertyName = "模组条码";
dgvcPoleCode.DataPropertyName = "极性编码";
dgvcModuleCategory.DataPropertyName = "模组类型";
}
/// <summary>
/// 显示推送消息
/// </summary>
/// <param name="msg"></param>
private void DisplayMessage(string msg)
{
this.BeginInvoke(new Action(() =>
{
if (rtxtMessage.TextLength > 20480)
{
rtxtMessage.Clear();
}
rtxtMessage.AppendText($"{DateTime.Now.ToString("HH:mm:ss.fff")}->{msg}\n");
rtxtMessage.ScrollToCaret();
}));
}
/// <summary>
/// 一行一行的更新数据库【耗时任务】
/// </summary>
/// <param name="dtImport"></param>
private Task<int> UpdateDatabase(DataTable dtImport)
{
int rowCount = dtImport.Rows.Count;
progressBarImport.Maximum = rowCount;
progressBarImport.Value = 0;//进度条清零
DisplayMessage($"开始导入模组极柱数据，准备导入数据条数【{rowCount}】......");
Task<int> task = Task.Run<int>(() =>
{
int cnt = 0;
for (int i = 0; i < rowCount; i++)
{
//更新进度条
this.BeginInvoke(new Action(() =>
{
if (this.IsHandleCreated)
{
progressBarImport.Value++;
}
}));
string ModuleBarcode = Convert.ToString(dtImport.Rows[i]["模组条码"]);
string PoleCode = Convert.ToString(dtImport.Rows[i]["极性编码"]);
string ModuleCategory = Convert.ToString(dtImport.Rows[i]["模组类型"]);
if (string.IsNullOrWhiteSpace(ModuleBarcode))
{
continue;
}
try
{
List<string> sqlCollection = new List<string>();
List<Dictionary<string, object>> dictCollection = new List<Dictionary<string, object>>();
sqlCollection.Add("delete from module_pole where ModuleBarcode=@ModuleBarcode");
sqlCollection.Add("insert into module_pole (ModuleBarcode,ModuleCategory,PoleCode,ProcessEndTime) values (@ModuleBarcode,@ModuleCategory,@PoleCode,@ProcessEndTime)");
dictCollection.Add(new Dictionary<string, object>() { { "ModuleBarcode", ModuleBarcode } });
dictCollection.Add(new Dictionary<string, object>() { { "ModuleBarcode", ModuleBarcode },
{ "ModuleCategory", ModuleCategory }, { "PoleCode", PoleCode }, { "ProcessEndTime", DateTime.Now } });
ExecuteTransaction(sqlCollection, dictCollection);
DisplayMessage($"导入模组极柱数据成功，模组条码【{ModuleBarcode}】");
cnt++;
}
catch (Exception ex)
{
DisplayMessage($"导入模组极柱数据出错【{ex.Message}】，模组条码【{ModuleBarcode}】");
}
}
return cnt;
});
return task;
}
/// <summary>
/// 这里执行事务
/// </summary>
/// <param name="sqlCollection"></param>
/// <param name="dictCollection"></param>
private void ExecuteTransaction(List<string> sqlCollection, List<Dictionary<string, object>> dictCollection)
{
Random random = new Random((int)DateTime.Now.Ticks);
int millisecondsTimeout = random.Next(100, 300);
System.Threading.Thread.Sleep(millisecondsTimeout);
DisplayMessage($"执行数据库事务，耗时【{millisecondsTimeout}】ms");
}
private async void btnSave_Click(object sender, EventArgs e)
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = "Excel文件|*.xls;*.xlsx";
DialogResult dialog = openFileDialog.ShowDialog();
if (dialog != DialogResult.OK)
{
return;
}
string fileName = openFileDialog.FileName;
try
{
DataTable dtImport = NpoiExcelOperateUtil.ExcelToTable(fileName);
if (!dtImport.Columns.Contains("序号"))
{
MessageBox.Show($"必须包含列【序号】,请检查excel格式.路径\n【{fileName}】", "提示");
return;
}
if (!dtImport.Columns.Contains("模组条码"))
{
MessageBox.Show($"必须包含列【模组条码】,请检查excel格式.路径\n【{fileName}】", "提示");
return;
}
if (!dtImport.Columns.Contains("极性编码"))
{
MessageBox.Show($"必须包含列【极性编码】,请检查excel格式.路径\n【{fileName}】", "提示");
return;
}
if (!dtImport.Columns.Contains("模组类型"))
{
MessageBox.Show($"必须包含列【模组类型】,请检查excel格式.路径\n【{fileName}】", "提示");
return;
}
//绑定网格数据
dgvData.DataSource = dtImport;
int rowCount = dtImport.Rows.Count;
if (rowCount < 1)
{
MessageBox.Show($"Excel不存在有效的上传数据配置行.路径\n【{fileName}】", "提示");
return;
}
Task<int> task = UpdateDatabase(dtImport);
await task;
DisplayMessage($"导入模组极柱数据成功，实际导入数据条数【{task.Result}】......");
}
catch (Exception ex)
{
MessageBox.Show($"读取excel出现异常，请检查是否是标准的Excel文件.【{ex.Message}】路径\n【{fileName}】", "出错");
return;
}
}
private void btnExport_Click(object sender, EventArgs e)
{
SaveFileDialog saveFileDialog = new SaveFileDialog();
saveFileDialog.FileName = DateTime.Now.ToString("yyyy-MM-dd-HHmmss") + ".xls";
saveFileDialog.Filter = "Excel文件|*.xls;*.xlsx";
DialogResult dialog = saveFileDialog.ShowDialog();
if (dialog != DialogResult.OK)
{
return;
}
string fileName = saveFileDialog.FileName;
DataTable dt = new DataTable("TableToExcel");
dt.Columns.Add("序号", typeof(int));
dt.Columns.Add("模组条码", typeof(string));
dt.Columns.Add("极性编码", typeof(string));
dt.Columns.Add("模组类型", typeof(string));
//最多保留3行
for (int i = 0; i < Math.Min(dgvData.Rows.Count, 3); i++)
{
dt.Rows.Add(dgvData[0, i].Value, dgvData[1, i].Value, dgvData[2, i].Value, dgvData[3, i].Value);
}
try
{
NpoiExcelOperateUtil.TableToExcel(dt, fileName);
MessageBox.Show($"保存示例模板成功，保存数据条数【{dt.Rows.Count}】.\n路径【{fileName}】", "提示");
}
catch (Exception ex)
{
MessageBox.Show($"保存示例模板出现异常，请检查是否是标准的Excel文件.【{ex.Message}】路径\n【{fileName}】", "出错");
return;
}
}
}
}
程序运行如图：
