小编Pat*_*ick的帖子

导出excel后,此代码总是跳过最后一行,你能检查一下代码中的错误吗？

我变了

transcationTableDataGridView.Rows.Count - 1

至

transcationTableDataGridView.Rows.Count + 1

它确实将所有行导出为ex​​cel但抛出索引应为非负错误此异常:

 private void exportToExcel_Click(object sender, EventArgs e)
        {
try
            {
                Microsoft.Office.Interop.Excel._Application app = new Microsoft.Office.Interop.Excel.Application();
                Microsoft.Office.Interop.Excel._Workbook workbook = app.Workbooks.Add(Type.Missing);
                Microsoft.Office.Interop.Excel._Worksheet worksheet = null;
                app.Visible = true;
                worksheet = workbook.Sheets["Sheet1"];
                worksheet = workbook.ActiveSheet;
                worksheet.Name = "Records";

                try
                {
                    for (int i = 1; i < transcationTableDataGridView.Columns.Count + 1; i++)
                    {
                        worksheet.Cells[1, i] = transcationTableDataGridView.Columns[i - 1].HeaderText;
                    }
                    for (int i = 0; i < transcationTableDataGridView.Rows.Count - 1; i++)
                    {
                        for (int j …

我正在尝试从另一个按钮调用 datagridview 单元格事件方法。

DataGridView 单元格双击方法

private void ListDataGridView_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
        {
            if (e.RowIndex >= 0)
            {
                ListDataGridView.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
                DataGridViewRow row = this.ListDataGridView.Rows[e.RowIndex];

                comboBox2.Text = row.Cells[1].Value.ToString();

            }
        }

这是我调用此方法的按钮

private void button6_Click(object sender, EventArgs e)
{
  ListDataGridView_CellDoubleClick(sender, e);
}

我收到的错误

错误 3 命名空间“System”中不存在类型或命名空间名称“DataGridViewCellEventHandler”（您是否缺少程序集引用？）C:\VisualC#\Projects\DataGridViewApplication\DataGridViewApplication\List.Designer.cs 340 46 DataGridViewApplication

我做了什么：

我将 EventArgs 更改为 DataGridViewCellEventArgs。

private void button6_Click(object sender, DataGridViewCellEventArgs e)
   {    
     ListDataGridView_CellDoubleClick(sender, e);
   }

现在我收到错误：

this.button6.Click += new System.EventHandler(this.button6_Click);

错误 3 “button6_Click”没有重载匹配委托“System.EventHandler”

C:\VisualC#\Projects\DataGridViewApplication\DataGridViewApplication\List.Designer.cs 340 35 DataGridViewApplication

现在我将按钮事件处理程序代码更改为此

this.button6.Click += new System.DataGridViewCellEventHandler(this.button6_Click);

仍然收到此错误并卡在此处 …

我是SQL Queries的新手,我想从SettlementTypeSetup(表)加载"PSX LAGA"值,其中结算类型等于Regular/BO,Sale/Purchase等于"Purchase";

下面是我的代码,这是我的表

private void Load_Settlement_Type()
        {
        SqlCeConnection conn = null;
        SqlCeCommand cmd = null;
        SqlCeDataReader rdr = null;

        try
        {
            conn =
                new SqlCeConnection(
                   @"Data Source=|DataDirectory|\Database.sdf;Persist Security Info=False");
            conn.Open();
            cmd = new SqlCeCommand("SELECT PSXLaga FROM SettlementTypeSetup where SettlementType=BO/REGULAR;" , conn);
            rdr = cmd.ExecuteReader();

            if (rdr == null)
            {
                MessageBox.Show("Reader is null");
            }
            else
            {
                while (rdr.Read())
                {
                    PSXLAGATEXT  = rdr["PSXLaga"].ToString();

                }

                 rdr.Close();
                cmd.Dispose();

            }
        }
        finally
        {
            conn.Close();
            PSXLagaTextBox.Text = PSXLAGATEXT;

        }

    }

****它给出了错误:列名:BO/REGULAR未找到,而BO/REGULAR不是列名,BO/REGULAR是SettlementType(Column)的值,条件应如下所示.**

给我PSX Laga Value,其中SettlementType(Column)值为BO/REGULAR,Sale/Purchase(Column)为Purchase.

**

• 我正在生成book serial no和保存到keyvalue对,然后保存到文本文件,每个键都是唯一的.

• 当我将它保存到文本文件时,生成密钥,我可以检索密钥,它工作正常.

• 当我生成第二个密钥并将其保存到文本文件时,它会覆盖文本文件并删除先前生成的密钥.

生成密钥:

private void GenerateButton1_Click(object sender, EventArgs e)
        {

            if (comboBox1.SelectedIndex == 0)
            {
                BookcomboBox2.Items.Clear();

                from = int.Parse(FrmtextBox1.Text);
                to = int.Parse(TotextBox2.Text);

                result = to - from;

                for (int i = 0; i <= result; i++)
                {
                    string item = Convert.ToString(from + i); 
                    BookcomboBox2.Items.Add(item);
                    vals.Add(new KeyValuePair<int, string>(0, item)); // 
                }
                MessageBox.Show("Book No 1,  Generated Successfully", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }

            if (comboBox1.SelectedIndex == 1)
            {
                BookcomboBox2.Items.Clear();

                from = int.Parse(FrmtextBox1.Text);
                to = int.Parse(TotextBox2.Text);

                result = to - from;

                for …

我已经尝试了几个小时，但在这个 sql 查询中找不到错误，出现异常“<”

            Connection con = new OrderManager.Connection();
            SqlCommand cmd = new SqlCommand(); 

            string query = @"INSERT INTO [MasterDatabase].[dbo].[Neworder]
           ([OrderID]
           ,[Date]
           ,[Customer_Name]
           ,[Quality]
           ,[Color]
           ,[PCs]
           ,[Cutting]
           ,[TotalYards])
     VALUES
           (<OrderID, nvarchar(50),>
           ,<Date, varchar(25),>
           ,<Customer_Name, varchar(25),>
           ,<Quality, varchar(25),>
           ,<Color, varchar(25),>
           ,<PCs, varchar(25),>
           ,<Cutting, varchar(25),>
           ,<TotalYards, varchar(25),>)";

            cmd = new SqlCommand(query, con.ActiveCon());

            cmd.Parameters.AddWithValue("@OrderID", TxtBox_OrderID.Text);
            cmd.Parameters.AddWithValue("@Date", dateTimePicker1.Value.ToString());
            cmd.Parameters.AddWithValue("@Customer_Name", txtbox_CusName.Text);
            cmd.Parameters.AddWithValue("@Quality", combo_Quality.Text);
            cmd.Parameters.AddWithValue("@Color", combo_Color.Text);
            cmd.Parameters.AddWithValue("@PCs", updown_PCs.Text);
            cmd.Parameters.AddWithValue("@Cutting", combo_Cutting.Text);
            cmd.Parameters.AddWithValue("@TotalYards", "Total Yards");

cmd.ExecuteNonQuery(); // 这是抛出错误的地方

            MessageBox.Show("Record Inserted", "Record Entered Successfully!");

我也尝试使用这个但同样的问题。

string query = @"INSERT INTO …