using OfficeOpenXml;
using System.Collections.Generic;
using System.Data;
using System.Windows.Forms;

namespace 口罩泄露定制款.Excle
{
    internal class UserExcleHelper
    {  //文件路径
        static string path = Application.StartupPath + @"\UserExcleHelper.xlsx";
        //向表格中写入用户数据
        public void WriteData(string username, string password, string quanxian)
        {
            bool isHave = false;
            ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
            //创建Excel对象
            ExcelPackage package = new ExcelPackage(new System.IO.FileInfo(path));
            // 获取第一个工作表，如果不存在则创建  
            ExcelWorksheet worksheet;
            if (package.Workbook.Worksheets.Count == 0)
            {
                worksheet = package.Workbook.Worksheets.Add("用户表");
                worksheet.Cells[1, 1].Value = "用户名";
                worksheet.Cells[1, 2].Value = "密码";
                worksheet.Cells[1, 3].Value = "用户权限";
                worksheet.Cells[2, 1].Value = "admin";
                worksheet.Cells[2, 2].Value = "admin123456";
                worksheet.Cells[2, 3].Value = "管理员";
            }
            else
            {
                worksheet = package.Workbook.Worksheets[0];
            }
            //判断用户名是否存在
            for (int i = 2; i <= worksheet.Dimension.Rows; i++)
            {
                if (worksheet.Cells[i, 1].Value.ToString() == username)
                {
                    isHave = true;
                    break;
                }
            }
            if (isHave)
            {
                MessageBox.Show("用户名已存在！");
                return;
            }
            else
            {
                int row = worksheet.Dimension.Rows + 1;
                worksheet.Cells[row, 1].Value = username;
                worksheet.Cells[row, 2].Value = password;
                worksheet.Cells[row, 3].Value = quanxian;
                //保存并关闭文件
                package.Save();
            }

        }
        //读取表格用户名数据
        public List<string> ReadUserNameData()
        {
            ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
            //创建Excel对象
            ExcelPackage package = new ExcelPackage(new System.IO.FileInfo(path));
            // 获取第一个工作表，如果不存在则创建  
            ExcelWorksheet worksheet;
            if (package.Workbook.Worksheets.Count == 0)
            {
               // WriteData("","","");
                return null;
            }
            else
            {
                worksheet = package.Workbook.Worksheets[0];
            }
            List<string> list = new List<string>();
            for (int i = 2; i <= worksheet.Dimension.Rows; i++)
            {
                list.Add(worksheet.Cells[i, 1].Value.ToString());
            }
            return list;
        }
        //读取所有单元格信息并存放在datatable中
        public DataTable ReadUserData()
        {
            ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
            //创建Excel对象
            ExcelPackage package = new ExcelPackage(new System.IO.FileInfo(path));
            // 获取第一个工作表，如果不存在则创建  
            ExcelWorksheet worksheet;
            if (package.Workbook.Worksheets.Count == 0)
            {
                return null;
            }
            else
            {
                worksheet = package.Workbook.Worksheets[0];
            }
            DataTable dt = new DataTable();
            dt.Columns.Add("用户名");
            dt.Columns.Add("密码");
            dt.Columns.Add("用户权限");
            for (int i = 2; i <= worksheet.Dimension.Rows; i++)
            {
                DataRow dr = dt.NewRow();
                dr["用户名"] = worksheet.Cells[i, 1].Value.ToString();
                dr["密码"] = worksheet.Cells[i, 2].Value.ToString();
                dr["用户权限"] = worksheet.Cells[i, 3].Value.ToString();
                dt.Rows.Add(dr);
            }
            return dt;
        }
        //修改用户信息
        public void UpdateUserData(int index, string username, string password, string quanxian)
        {
            ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
            //创建Excel对象
            ExcelPackage package = new ExcelPackage(new System.IO.FileInfo(path));
            // 获取第一个工作表，如果不存在则创建  
            ExcelWorksheet worksheet;
            if (package.Workbook.Worksheets.Count == 0)
            {
                return;
            }
            else
            {
                worksheet = package.Workbook.Worksheets[0];
            }

            worksheet.Cells[index, 1].Value = username;
            worksheet.Cells[index, 2].Value = password;
            worksheet.Cells[index, 3].Value = quanxian;

            //保存并关闭文件
            package.Save();
        }
        //删除用户信息
        public void DeleteUserData(int index)
        {
            ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
            //创建Excel对象
            ExcelPackage package = new ExcelPackage(new System.IO.FileInfo(path));
            // 获取第一个工作表，如果不存在则创建  
            ExcelWorksheet worksheet;
            if (package.Workbook.Worksheets.Count == 0)
            {
                return;
            }
            else
            {
                worksheet = package.Workbook.Worksheets[0];
            }
            //删除指定行
            worksheet.DeleteRow(index);
            //保存并关闭文件
            package.Save();
        }
    }
}