带定时器的数据网格 [英] Data Grids With a Timer

问题描述

大家好

是否可以通过计时器将不同的数据文件加载到数据网格中？例如，我有两张电子表格。我想加载第一张电子表格并让它在那里停留约5秒左右。然后在那5秒后，我希望第二个
电子表格加载代替第一个。这可能与1个数据网格有关，还是需要多个？

感谢任何建议

解决方案

您好，

这远非完美。在这种情况下，我正在读一个Excel文件，每五秒显示一个工作表。

后端

使用System; 
使用System.Collections.Generic; 
使用System.Data; 
使用System.Data.OleDb; 
使用System.IO; 
使用System.Linq; 
 
命名空间ExcelDemo_cs 
 {
公共类操作
 {
私有字符串FileName = Path.Combine（AppDomain.CurrentDomain.BaseDirectory，" SampleDataForPost.xlsx" ）; 
 public List< string> SheetNames = new List< string>（）; 
 public Operations（）
 {
 GetSheetNames（）; 
} 
 public void GetSheetNames（）
 {
 using（OleDbConnection cn = new OleDbConnection {ConnectionString = ConnectionString（FileName，" No"）}）
 {
 cn.Open（）; 
 DataTable Sheets = cn.GetOleDbSchemaTable（OleDbSchemaGuid.Tables，null）; 
 SheetNames = cn.GetOleDbSchemaTable（OleDbSchemaGuid.Tables，null）.AsEnumerable（）。Select（row => row.Field< string>（" TABLE_NAME"））。ToList（）; 
} 
 
} 
 public string ConnectionString（string FileName，string Header）
 {
 OleDbConnectionStringBuilder Builder = new OleDbConnectionStringBuilder（）; 
 if（Path.GetExtension（FileName）.ToUpper（）==" .XLS"）
 {
 Builder.Provider =" Microsoft.Jet.OLEDB.4.0" ;; 
 Builder.Add（" Extended Properties"，string.Format（" Excel 8.0; IMEX = 1; HDR = {0};"，Header））; 
} 
 else 
 {
 Builder.Provider =" Microsoft.ACE.OLEDB.12.0" ;; 
 Builder.Add（" Extended Properties"，string.Format（" Excel 12.0; IMEX = 1; HDR = {0};"，Header））; 
} 
 
 Builder.DataSource = FileName; 
 
返回Builder.ConnectionString; 
} 
 public DataTable LoadSheet（string SheetName）
 {
 DataTable dt = new DataTable（）; 
 using（OleDbConnection cn = new OleDbConnection {ConnectionString = ConnectionString（FileName，" No"）}）
 {
 cn.Open（）; 
 
使用（OleDbCommand cmd = new OleDbCommand {CommandText = 

" SELECT * FROM [{SheetName}]"，Connection = cn}）
{
OleDbDataReader dr = cmd.ExecuteReader（）;
dt.Load（dr）;
}

返回dt;
}

}

}
}

前端代码

使用System; 
使用System.Threading.Tasks; 
使用System.Windows.Forms; 
 
命名空间ExcelDemo_cs 
 {
公共部分类Form1：表格
 {
操作ops = new Operations（）; 
 static System.Timers.Timer aTimer; 
 
 void SetTimer（）
 {
 aTimer = new System.Timers.Timer（10）; 
 aTimer.Elapsed + = async（sender，e）=>等待HandleTimer（）; 
 aTimer.AutoReset = true; 
 aTimer.Enabled = true; 
} 
异步任务< int> HandleTimer（）
 {
 aTimer.Stop（）; 
 for（int sheetIndex = 0; sheetIndex< ops.SheetNames.Count; sheetIndex ++）
 {
 if（dataGridView1.InvokeRequired）
 {
 dataGridView1.Invoke（新的MethodInvoker（
委托
 {
 dataGridView1.DataSource = ops.LoadSheet（ops.SheetNames [sheetIndex]）; 
}））; 
 
 await Task.Delay（5000）; 
} 
} 
 
 aTimer.Dispose（）; 
返回0; 
} 
 public Form1（）
 {
 InitializeComponent（）; 
显示+ = Form1_Shown; 
} 
 private void Form1_Shown（object sender，EventArgs e）
 {
 SetTimer（）; 
} 
} 
} 
 

当然要做多个文件，你需要逻辑才能做到这一点。无论如何要考虑但不符合您的全部要求。

Hi Everyone

Is it possible to load different files of data into a data grid via timer? For example I have two spread sheets. I want to load in the first spread sheet and have it stay there for about 5 seconds or so. Then after those 5 seconds I would like the second spreadsheet to load in place of the first. Is this possible to do with 1 data grid or do I need multiple ones?

Thanks For Any Advice

解决方案

Hello,

This is far from perfect. In this case I'm reading one Excel file, each five seconds shows a WorkSheet.

Backend

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.OleDb;
using System.IO;
using System.Linq;

namespace ExcelDemo_cs
{
    public class Operations
    {
        private string FileName = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "SampleDataForPost.xlsx");
        public List<string> SheetNames = new List<string>();
        public Operations()
        {
            GetSheetNames();
        }
        public void GetSheetNames()
        {
            using (OleDbConnection cn = new OleDbConnection { ConnectionString = ConnectionString(FileName, "No") })
            {
                cn.Open();
                DataTable Sheets = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                SheetNames = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null).AsEnumerable().Select(row => row.Field<string>("TABLE_NAME")).ToList();
            }

        }
        public string ConnectionString(string FileName, string Header)
        {
            OleDbConnectionStringBuilder Builder = new OleDbConnectionStringBuilder();
            if (Path.GetExtension(FileName).ToUpper() == ".XLS")
            {
                Builder.Provider = "Microsoft.Jet.OLEDB.4.0";
                Builder.Add("Extended Properties", string.Format("Excel 8.0;IMEX=1;HDR={0};", Header));
            }
            else
            {
                Builder.Provider = "Microsoft.ACE.OLEDB.12.0";
                Builder.Add("Extended Properties", string.Format("Excel 12.0;IMEX=1;HDR={0};", Header));
            }

            Builder.DataSource = FileName;

            return Builder.ConnectionString;
        }
        public DataTable LoadSheet(string SheetName)
        {
            DataTable dt = new DataTable();
            using (OleDbConnection cn = new OleDbConnection { ConnectionString = ConnectionString(FileName, "No") })
            {
                cn.Open();

                using (OleDbCommand cmd = new OleDbCommand { CommandText =

"SELECT * FROM [{SheetName}]", Connection = cn }) { OleDbDataReader dr = cmd.ExecuteReader(); dt.Load(dr); } return dt; } } } }

Front end code

using System;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace ExcelDemo_cs
{
    public partial class Form1 : Form
    {
        Operations ops = new Operations();
        static System.Timers.Timer aTimer;

        void SetTimer()
        {
            aTimer = new System.Timers.Timer(10);
            aTimer.Elapsed += async (sender, e) => await HandleTimer();
            aTimer.AutoReset = true;
            aTimer.Enabled = true;
        }
        async Task<int> HandleTimer()
        {
            aTimer.Stop();
            for (int sheetIndex = 0; sheetIndex < ops.SheetNames.Count; sheetIndex++)
            {
                if (dataGridView1.InvokeRequired)
                {
                    dataGridView1.Invoke(new MethodInvoker(
                        delegate 
                        {
                            dataGridView1.DataSource = ops.LoadSheet(ops.SheetNames[sheetIndex]);
                        }));

                    await Task.Delay(5000);
                }
            }

            aTimer.Dispose();
            return 0;
        }
        public Form1()
        {
            InitializeComponent();
            Shown += Form1_Shown;
        }
         private void Form1_Shown(object sender, EventArgs e)
        {
            SetTimer();
        }
    }
}

Of course to do multiple files you need logic on top of the above to do that. Anyways something to consider but does not meet your full requirements.

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