我有一个包含客户表和代理表的 .mdb 文件.Agents 表目前唯一要做的就是为每个客户填充 Agent 下拉列表...

I have a .mdb file with a Customers table and an Agents table. The only thing that the Agents table does as yet is populate the Agent dropdown for each customer...

我有一个链接到 customerBindingSource 的 DataGridView.customerBindingSource 的 DataMember 设置为 Customer，DataSource 设置为 bindingSource1.这将 DataSource 设置为 customerAppDS21.如果我选择 customerAppDS21 并在 DataSet Designer 中单击 Edit，我可以很清楚地看到有一个 Customer 表和 Agent 表.这些是直接从 Data.mdf > Tables 文件夹中拖出来的.我已经完成了配置向导并检查了更新、插入和删除命令是否正确生成.

I have a DataGridView linked to the customerBindingSource. The customerBindingSource has DataMember set to Customer and DataSource set to bindingSource1. This has the DataSource set to customerAppDS21. If I select customerAppDS21 and click Edit in DataSet Designer I can quite clearly see that there is a Customer table and Agent table. These were dragged directly from the Data.mdf > Tables folder. I have been through the Configure wizard and checked that the Update, Insert and Delete commands are generated correctly.

当用户离开一行或添加一行时，我正在设置唯一 ID (GUID)(我认为两者都不需要，但我非常怀疑这是问题的原因).用户可以更新或添加尽可能多的行.当用户单击保存按钮时，它会调用 customerTableAdapter.Update(customerAppDS21.Customer);.所有的事件肯定是正确连接的.

I am setting the unique ID (GUID) when the user leaves a row or adds a row (I dont think both are needed, but I very much doubt this is the cause of the problem). The user can update or add as many rows as possible. When the user clicks the Save button it calls customerTableAdapter.Update(customerAppDS21.Customer);. All the events are definitely wired up correctly.

问题基本上是数据集似乎得到了更新但数据库本身没有更新.我可以关闭程序并立即重新加载它，数据就在那里.但是，如果我对代码进行任何更改，然后重新编译并加载程序，所有数据都消失了.这就是让我认为 DataSet 正在更新而不是数据库的原因.

The problem is basically that the DataSet appears to get updated but the database itself is not updated. I can close the program and reload it straight away and the data is there. However if I make any changes to the code and then recompile and load the program all the data is gone. This is what makes me think the DataSet is being updated but not the database.

有人知道如何解决这个问题吗?我尝试在 .Update(bla); 行之前和之后添加 .acceptChanges(); 行，但没有成功.我还尝试在 .Update(bla); 行之前调用 customerBindingSource.EndEdit(); 和 bindingSource1.EndEdit();.

Does anyone have any idea how to solve the problem? I have tried adding the .acceptChanges(); line both before and after the .Update(bla); line, with no success. I have also tried calling customerBindingSource.EndEdit(); and bindingSource1.EndEdit(); before the .Update(bla); line.

对此的任何帮助将不胜感激.我已经遇到这个问题 2 天了，并尝试了很多教程来提示我哪里出错了.

Any help with this would be greatly appreciated. I have had this problem for 2 days now and tried alsorts of tutorials to get a hint on where I am going wrong.

问候，

理查德

更新:以下代码...

void button1_Click(object sender, EventArgs e)
{
    Validate();
    customerBindingSource.EndEdit();
    customerTableAdapter.Update(customerAppDS21.Customer);
}

void grdCustomers_RowLeave(object sender, DataGridViewCellEventArgs e)
{
    DataGridViewRow gvr = grdCustomers.Rows[e.RowIndex];
    if (gvr.Cells[0].Value == null)
    {
        String g = Guid.NewGuid().ToString();
        gvr.Cells[0].Value = g;
    }
    else
    {
        String currID = gvr.Cells[0].Value.ToString();
        if (currID.Equals(""))
        {
            String g = Guid.NewGuid().ToString();
            gvr.Cells[0].Value = g;
        }
    }
}

void grdCustomers_UserAddedRow(object sender, DataGridViewRowEventArgs e)
{
    DataGridViewRow gvr = grdCustomers.Rows[grdCustomers.SelectedCells[0].RowIndex];
    if (gvr.Cells[0].Value == null)
    {
        String g = Guid.NewGuid().ToString();
        gvr.Cells[0].Value = g;
    }
    else
    {
        String currID = gvr.Cells[0].Value.ToString();
        if (currID.Equals(""))
        {
            String g = Guid.NewGuid().ToString();
            gvr.Cells[0].Value = g;
        }
    }
}

设计器代码(对不起，它太长了 - 我不想冒险错过任何重要的东西):

Designer code (sorry its so long - I dont want to risk missing out anything vital):

namespace CustomerApp
{
    partial class CustomerAppForm
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.components = new System.ComponentModel.Container();
            System.Windows.Forms.DataGridViewCellStyle dataGridViewCellStyle1 = new System.Windows.Forms.DataGridViewCellStyle();
            System.Windows.Forms.DataGridViewCellStyle dataGridViewCellStyle2 = new System.Windows.Forms.DataGridViewCellStyle();
            System.Windows.Forms.DataGridViewCellStyle dataGridViewCellStyle3 = new System.Windows.Forms.DataGridViewCellStyle();
            this.tabControl1 = new System.Windows.Forms.TabControl();
            this.tabPage1 = new System.Windows.Forms.TabPage();
            this.button1 = new System.Windows.Forms.Button();
            this.grdCustomers = new System.Windows.Forms.DataGridView();
            this.agentBindingSource = new System.Windows.Forms.BindingSource(this.components);
            this.bindingSource1 = new System.Windows.Forms.BindingSource(this.components);
            this.customerAppDS21 = new CustomerApp.CustomerAppDS2();
            this.tabPage2 = new System.Windows.Forms.TabPage();
            this.customerTableAdapter = new CustomerApp.CustomerAppDS2TableAdapters.CustomerTableAdapter();
            this.agentTableAdapter = new CustomerApp.CustomerAppDS2TableAdapters.AgentTableAdapter();
            this.customerBindingSource = new System.Windows.Forms.BindingSource(this.components);
            this.idDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companynameDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.contactforenameDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.contactsurnameDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companyaddress1DataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companyaddress2DataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companytownDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companycountyDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.companypostcodeDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.contacttelephoneDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.contactfaxDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.contactemailDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.agentIDDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewComboBoxColumn();
            this.contactfullnameDataGridViewTextBoxColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();
            this.tabControl1.SuspendLayout();
            this.tabPage1.SuspendLayout();
            ((System.ComponentModel.ISupportInitialize)(this.grdCustomers)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.agentBindingSource)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.customerAppDS21)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.customerBindingSource)).BeginInit();
            this.SuspendLayout();
            // 
            // tabControl1
            // 
            this.tabControl1.Controls.Add(this.tabPage1);
            this.tabControl1.Controls.Add(this.tabPage2);
            this.tabControl1.Location = new System.Drawing.Point(12, 12);
            this.tabControl1.Name = "tabControl1";
            this.tabControl1.SelectedIndex = 0;
            this.tabControl1.Size = new System.Drawing.Size(1000, 640);
            this.tabControl1.TabIndex = 0;
            // 
            // tabPage1
            // 
            this.tabPage1.Controls.Add(this.button1);
            this.tabPage1.Controls.Add(this.grdCustomers);
            this.tabPage1.Location = new System.Drawing.Point(4, 22);
            this.tabPage1.Name = "tabPage1";
            this.tabPage1.Padding = new System.Windows.Forms.Padding(3);
            this.tabPage1.Size = new System.Drawing.Size(992, 614);
            this.tabPage1.TabIndex = 0;
            this.tabPage1.Text = "Customers";
            this.tabPage1.UseVisualStyleBackColor = true;
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(882, 462);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 23);
            this.button1.TabIndex = 1;
            this.button1.Text = "Save";
            this.button1.UseVisualStyleBackColor = true;
            // 
            // grdCustomers
            // 
            this.grdCustomers.AllowUserToOrderColumns = true;
            this.grdCustomers.AutoGenerateColumns = false;
            dataGridViewCellStyle1.Alignment = System.Windows.Forms.DataGridViewContentAlignment.MiddleLeft;
            dataGridViewCellStyle1.BackColor = System.Drawing.SystemColors.Control;
            dataGridViewCellStyle1.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            dataGridViewCellStyle1.ForeColor = System.Drawing.SystemColors.WindowText;
            dataGridViewCellStyle1.SelectionBackColor = System.Drawing.SystemColors.Highlight;
            dataGridViewCellStyle1.SelectionForeColor = System.Drawing.SystemColors.HighlightText;
            dataGridViewCellStyle1.WrapMode = System.Windows.Forms.DataGridViewTriState.True;
            this.grdCustomers.ColumnHeadersDefaultCellStyle = dataGridViewCellStyle1;
            this.grdCustomers.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
            this.grdCustomers.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
            this.idDataGridViewTextBoxColumn,
            this.companynameDataGridViewTextBoxColumn,
            this.contactforenameDataGridViewTextBoxColumn,
            this.contactsurnameDataGridViewTextBoxColumn,
            this.companyaddress1DataGridViewTextBoxColumn,
            this.companyaddress2DataGridViewTextBoxColumn,
            this.companytownDataGridViewTextBoxColumn,
            this.companycountyDataGridViewTextBoxColumn,
            this.companypostcodeDataGridViewTextBoxColumn,
            this.contacttelephoneDataGridViewTextBoxColumn,
            this.contactfaxDataGridViewTextBoxColumn,
            this.contactemailDataGridViewTextBoxColumn,
            this.agentIDDataGridViewTextBoxColumn,
            this.contactfullnameDataGridViewTextBoxColumn});
            this.grdCustomers.DataSource = this.customerBindingSource;
            dataGridViewCellStyle2.Alignment = System.Windows.Forms.DataGridViewContentAlignment.MiddleLeft;
            dataGridViewCellStyle2.BackColor = System.Drawing.SystemColors.Window;
            dataGridViewCellStyle2.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            dataGridViewCellStyle2.ForeColor = System.Drawing.SystemColors.ControlText;
            dataGridViewCellStyle2.SelectionBackColor = System.Drawing.SystemColors.Highlight;
            dataGridViewCellStyle2.SelectionForeColor = System.Drawing.SystemColors.HighlightText;
            dataGridViewCellStyle2.WrapMode = System.Windows.Forms.DataGridViewTriState.False;
            this.grdCustomers.DefaultCellStyle = dataGridViewCellStyle2;
            this.grdCustomers.Location = new System.Drawing.Point(3, 3);
            this.grdCustomers.Name = "grdCustomers";
            dataGridViewCellStyle3.Alignment = System.Windows.Forms.DataGridViewContentAlignment.MiddleLeft;
            dataGridViewCellStyle3.BackColor = System.Drawing.SystemColors.Control;
            dataGridViewCellStyle3.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            dataGridViewCellStyle3.ForeColor = System.Drawing.SystemColors.WindowText;
            dataGridViewCellStyle3.SelectionBackColor = System.Drawing.SystemColors.Highlight;
            dataGridViewCellStyle3.SelectionForeColor = System.Drawing.SystemColors.HighlightText;
            dataGridViewCellStyle3.WrapMode = System.Windows.Forms.DataGridViewTriState.True;
            this.grdCustomers.RowHeadersDefaultCellStyle = dataGridViewCellStyle3;
            this.grdCustomers.RowTemplate.DefaultCellStyle.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(255)))), ((int)(((byte)(192)))));
            this.grdCustomers.RowTemplate.DefaultCellStyle.Padding = new System.Windows.Forms.Padding(2);
            this.grdCustomers.RowTemplate.DefaultCellStyle.SelectionBackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(224)))), ((int)(((byte)(192)))));
            this.grdCustomers.Size = new System.Drawing.Size(983, 605);
            this.grdCustomers.TabIndex = 0;
            // 
            // agentBindingSource
            // 
            this.agentBindingSource.DataMember = "Agent";
            this.agentBindingSource.DataSource = this.bindingSource1;
            // 
            // bindingSource1
            // 
            this.bindingSource1.AllowNew = true;
            this.bindingSource1.DataSource = this.customerAppDS21;
            this.bindingSource1.Position = 0;
            // 
            // customerAppDS21
            // 
            this.customerAppDS21.DataSetName = "CustomerAppDS2";
            this.customerAppDS21.SchemaSerializationMode = System.Data.SchemaSerializationMode.IncludeSchema;
            // 
            // tabPage2
            // 
            this.tabPage2.Location = new System.Drawing.Point(4, 22);
            this.tabPage2.Name = "tabPage2";
            this.tabPage2.Padding = new System.Windows.Forms.Padding(3);
            this.tabPage2.Size = new System.Drawing.Size(992, 614);
            this.tabPage2.TabIndex = 1;
            this.tabPage2.Text = "Agents";
            this.tabPage2.UseVisualStyleBackColor = true;
            // 
            // customerTableAdapter
            // 
            this.customerTableAdapter.ClearBeforeFill = true;
            // 
            // agentTableAdapter
            // 
            this.agentTableAdapter.ClearBeforeFill = true;
            // 
            // customerBindingSource
            // 
            this.customerBindingSource.DataMember = "Customer";
            this.customerBindingSource.DataSource = this.bindingSource1;
            // 
            // idDataGridViewTextBoxColumn
            // 
            this.idDataGridViewTextBoxColumn.DataPropertyName = "id";
            this.idDataGridViewTextBoxColumn.HeaderText = "id";
            this.idDataGridViewTextBoxColumn.Name = "idDataGridViewTextBoxColumn";
            this.idDataGridViewTextBoxColumn.ReadOnly = true;
            // 
            // companynameDataGridViewTextBoxColumn
            // 
            this.companynameDataGridViewTextBoxColumn.DataPropertyName = "company_name";
            this.companynameDataGridViewTextBoxColumn.HeaderText = "Company Name";
            this.companynameDataGridViewTextBoxColumn.Name = "companynameDataGridViewTextBoxColumn";
            this.companynameDataGridViewTextBoxColumn.ToolTipText = "The name of the company";
            // 
            // contactforenameDataGridViewTextBoxColumn
            // 
            this.contactforenameDataGridViewTextBoxColumn.DataPropertyName = "contact_forename";
            this.contactforenameDataGridViewTextBoxColumn.HeaderText = "Contact Forename";
            this.contactforenameDataGridViewTextBoxColumn.Name = "contactforenameDataGridViewTextBoxColumn";
            // 
            // contactsurnameDataGridViewTextBoxColumn
            // 
            this.contactsurnameDataGridViewTextBoxColumn.DataPropertyName = "contact_surname";
            this.contactsurnameDataGridViewTextBoxColumn.HeaderText = "Contact Surname";
            this.contactsurnameDataGridViewTextBoxColumn.Name = "contactsurnameDataGridViewTextBoxColumn";
            // 
            // companyaddress1DataGridViewTextBoxColumn
            // 
            this.companyaddress1DataGridViewTextBoxColumn.DataPropertyName = "company_address1";
            this.companyaddress1DataGridViewTextBoxColumn.HeaderText = "Address 1";
            this.companyaddress1DataGridViewTextBoxColumn.Name = "companyaddress1DataGridViewTextBoxColumn";
            // 
            // companyaddress2DataGridViewTextBoxColumn
            // 
            this.companyaddress2DataGridViewTextBoxColumn.DataPropertyName = "company_address2";
            this.companyaddress2DataGridViewTextBoxColumn.HeaderText = "Address 2";
            this.companyaddress2DataGridViewTextBoxColumn.Name = "companyaddress2DataGridViewTextBoxColumn";
            // 
            // companytownDataGridViewTextBoxColumn
            // 
            this.companytownDataGridViewTextBoxColumn.DataPropertyName = "company_town";
            this.companytownDataGridViewTextBoxColumn.HeaderText = "Town";
            this.companytownDataGridViewTextBoxColumn.Name = "companytownDataGridViewTextBoxColumn";
            // 
            // companycountyDataGridViewTextBoxColumn
            // 
            this.companycountyDataGridViewTextBoxColumn.DataPropertyName = "company_county";
            this.companycountyDataGridViewTextBoxColumn.HeaderText = "County";
            this.companycountyDataGridViewTextBoxColumn.Name = "companycountyDataGridViewTextBoxColumn";
            // 
            // companypostcodeDataGridViewTextBoxColumn
            // 
            this.companypostcodeDataGridViewTextBoxColumn.DataPropertyName = "company_postcode";
            this.companypostcodeDataGridViewTextBoxColumn.HeaderText = "Postcode";
            this.companypostcodeDataGridViewTextBoxColumn.Name = "companypostcodeDataGridViewTextBoxColumn";
            // 
            // contacttelephoneDataGridViewTextBoxColumn
            // 
            this.contacttelephoneDataGridViewTextBoxColumn.DataPropertyName = "contact_telephone";
            this.contacttelephoneDataGridViewTextBoxColumn.HeaderText = "Telephone";
            this.contacttelephoneDataGridViewTextBoxColumn.Name = "contacttelephoneDataGridViewTextBoxColumn";
            // 
            // contactfaxDataGridViewTextBoxColumn
            // 
            this.contactfaxDataGridViewTextBoxColumn.DataPropertyName = "contact_fax";
            this.contactfaxDataGridViewTextBoxColumn.HeaderText = "Fax";
            this.contactfaxDataGridViewTextBoxColumn.Name = "contactfaxDataGridViewTextBoxColumn";
            // 
            // contactemailDataGridViewTextBoxColumn
            // 
            this.contactemailDataGridViewTextBoxColumn.DataPropertyName = "contact_email";
            this.contactemailDataGridViewTextBoxColumn.HeaderText = "Email";
            this.contactemailDataGridViewTextBoxColumn.Name = "contactemailDataGridViewTextBoxColumn";
            // 
            // agentIDDataGridViewTextBoxColumn
            // 
            this.agentIDDataGridViewTextBoxColumn.DataPropertyName = "agentID";
            this.agentIDDataGridViewTextBoxColumn.DataSource = this.agentBindingSource;
            this.agentIDDataGridViewTextBoxColumn.DisplayMember = "contact_fullname";
            this.agentIDDataGridViewTextBoxColumn.HeaderText = "agentID";
            this.agentIDDataGridViewTextBoxColumn.Name = "agentIDDataGridViewTextBoxColumn";
            this.agentIDDataGridViewTextBoxColumn.Resizable = System.Windows.Forms.DataGridViewTriState.True;
            this.agentIDDataGridViewTextBoxColumn.SortMode = System.Windows.Forms.DataGridViewColumnSortMode.Automatic;
            this.agentIDDataGridViewTextBoxColumn.ValueMember = "id";
            // 
            // contactfullnameDataGridViewTextBoxColumn
            // 
            this.contactfullnameDataGridViewTextBoxColumn.DataPropertyName = "contact_fullname";
            this.contactfullnameDataGridViewTextBoxColumn.HeaderText = "contact_fullname";
            this.contactfullnameDataGridViewTextBoxColumn.Name = "contactfullnameDataGridViewTextBoxColumn";
            this.contactfullnameDataGridViewTextBoxColumn.ReadOnly = true;
            this.contactfullnameDataGridViewTextBoxColumn.Visible = false;
            // 
            // CustomerAppForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(1184, 662);
            this.Controls.Add(this.tabControl1);
            this.Location = new System.Drawing.Point(100, 100);
            this.Name = "CustomerAppForm";
            this.StartPosition = System.Windows.Forms.FormStartPosition.Manual;
            this.Text = "Heritage Art Papers Ltd - Customer Application";
            this.Load += new System.EventHandler(this.CustomerAppForm_Load);
            this.tabControl1.ResumeLayout(false);
            this.tabPage1.ResumeLayout(false);
            ((System.ComponentModel.ISupportInitialize)(this.grdCustomers)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.agentBindingSource)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.customerAppDS21)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.customerBindingSource)).EndInit();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.TabControl tabControl1;
        private System.Windows.Forms.TabPage tabPage1;
        private System.Windows.Forms.TabPage tabPage2;
        private System.Windows.Forms.BindingSource bindingSource1;
        private CustomerAppDS2 customerAppDS21;
        private System.Windows.Forms.BindingSource agentBindingSource;
        private CustomerAppDS2TableAdapters.CustomerTableAdapter customerTableAdapter;
        private CustomerAppDS2TableAdapters.AgentTableAdapter agentTableAdapter;
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.BindingSource customerBindingSource;
        private System.Windows.Forms.DataGridViewTextBoxColumn idDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companynameDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contactforenameDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contactsurnameDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companyaddress1DataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companyaddress2DataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companytownDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companycountyDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn companypostcodeDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contacttelephoneDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contactfaxDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contactemailDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewComboBoxColumn agentIDDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridViewTextBoxColumn contactfullnameDataGridViewTextBoxColumn;
        private System.Windows.Forms.DataGridView grdCustomers;

    }
}

推荐答案

我想这可能是你的问题.非常仔细地阅读这两篇文章.第一个包含一个线程，建议在第二个链接(我在下面给出)中.

I guess this might be your problem. Read these two articles very carefully. The first one contains a thread where in the second link (I gave below) is suggested.

http://www.devnewsgroups.net/组/microsoft.public.dotnet.framework.adonet/topic58794.aspx

和

http://msdn.microsoft.com/en-us/library/ms246989.aspx

在第一个链接中，阅读 Kerry Moorman 的答案.

In the first link, read the answer of: Kerry Moorman.