C# 操作NPOI导入导出

//把T_Seats中的输入导出到Excel
private void button3_Click(object sender, EventArgs e)
{
//1.读取
string sql = "select * from T_Seats";
using (SqlDataReader reader = SqlHelper.ExecuteReader(sql, CommandType.Text))
{
if (reader.HasRows)
{

//创建Workbook
IWorkbook wk = new HSSFWorkbook();

//创建Sheet
ISheet sheet = wk.CreateSheet("T_Seats");

int rowIndex = 0;

#region 读取并创建每一行

//读取每一条数据
while (reader.Read())
{
//CC_AutoId, CC_LoginId, CC_LoginPassword, CC_UserName, CC_ErrorTimes, CC_LockDateTime, CC_TestInt
int autoId = reader.GetInt32(0);
string uid = reader.GetString(1);
string pwd = reader.GetString(2);
string name = reader.GetString(3);
int errorTimes = reader.GetInt32(4);
DateTime? lockDate = reader.IsDBNull(5) ? null : (DateTime?)reader.GetDateTime(5);
int? testInt = reader.IsDBNull(6) ? null : (int?)reader.GetInt32(6);

IRow row = sheet.CreateRow(rowIndex);
rowIndex++;

//像行中创建单元格
row.CreateCell(0).SetCellValue(autoId);
row.CreateCell(1).SetCellValue(uid);
row.CreateCell(2).SetCellValue(pwd);
row.CreateCell(3).SetCellValue(name);
row.CreateCell(4).SetCellValue(errorTimes);

//对于数据库中的空值，向单元格中插入空内容
ICell cellLockDate = row.CreateCell(5);
if (lockDate == null)
{
//设置单元格的数据类型为Blank，表示空单元格
cellLockDate.SetCellType(CellType.BLANK);
}
else
{
cellLockDate.SetCellValue((DateTime)lockDate);

//创建一个单元格格式对象
ICellStyle cellStyle = wk.CreateCellStyle();
cellStyle.DataFormat = HSSFDataFormat.GetBuiltinFormat("m/d/yy h:mm");
//设置当前日期这个单元格的是CellStyle属性
cellLockDate.CellStyle = cellStyle;

}
ICell cellTestInt = row.CreateCell(6);
if (testInt == null)
{
cellTestInt.SetCellType(CellType.BLANK);
}
else
{
cellTestInt.SetCellValue((int)testInt);
}

}
#endregion

//将Excel写入文件
using (FileStream fsWrite = File.OpenWrite("tseats.xls"))
{
wk.Write(fsWrite);
}
}
}

MessageBox.Show("操作完毕！");
//2.写Excel
}

//把Excel的内容导入到数据库表T_Seats
private void button4_Click(object sender, EventArgs e)
{
using (FileStream fsRead = File.OpenRead("tseats.xls"))
{
//1.读取Excel
IWorkbook wk = new HSSFWorkbook(fsRead);
ISheet sheet = wk.GetSheetAt(0);

string sql_insert = "insert into T_Seats values(@uid,@pwd,@uname,@errorTimes,@lockDate,@testint)";

//读取sheet中的每一行
for (int r = 0; r <= sheet.LastRowNum; r++)
{

//读取每行
IRow row = sheet.GetRow(r);
//读取除了第一列的其他几列
string loginId = row.GetCell(1).StringCellValue;
string password = row.GetCell(2).StringCellValue;
string username = row.GetCell(3).StringCellValue;
int errorTimes = (int)row.GetCell(4).NumericCellValue;
double? lockDate = null;
ICell cellLockDate = row.GetCell(5);
if (cellLockDate != null && cellLockDate.CellType != CellType.BLANK)
{
lockDate = row.GetCell(5).NumericCellValue;
}
else
{
//lockDate = null;
}

int? testInt = null;
ICell cellTestInt = row.GetCell(6);

if (cellTestInt != null && cellTestInt.CellType != CellType.BLANK)
{
testInt = (int)cellTestInt.NumericCellValue;
}
else
{
//testInt = null;
}

SqlParameter[] pms = new SqlParameter[] {
new SqlParameter("@uid",loginId),
new SqlParameter("@pwd",password),
new SqlParameter("@uname",username),
new SqlParameter("@errorTimes",errorTimes),

new SqlParameter("@lockDate",lockDate==null?DBNull.Value:(object)DateTime.FromOADate((double)lockDate)),
new SqlParameter("@testint",testInt==null?DBNull.Value:(object)testInt),
};
//执行插入操作
SqlHelper.ExecuteNonQuery(sql_insert, CommandType.Text, pms);
}
}
MessageBox.Show("ok");

//2.向表T_Seats执行insert语句
}
}