C#使用Command将dataGrideView表格内数据与数据库交互

本文主要介绍通过Command类使用SQL插入指令insert与查询指令select将dataGrideView表格内添加至数据库，与从数据库读出数据存放在dataGrideView表格中。

C#制作的界面如下：(制作过程不再详述)

• 点击"创建数据"按钮，将姓名、性别、年龄文本框中的数据写入表格；
• 点击"存入数据库"按钮，将表格中数据存入数据库，存入成功后将表格内容清除；
• 点击"读取数据"按钮，将读取数据库中的内容并添加到表格中。

在编程之前向使用SQL Server创建数据库：mydb001，并在数据库中创建数据表：mytable001;

在数据表mytable001中添加列信息：ID(主键、自动赋值)、姓名(nvarchar(20))、性别(nvarchar(5))、年龄(int)。

如图：

C#代码如下：

 using System;
 using System.Windows.Forms;
 using System.Data.SqlClient;

 namespace 使用Command将表格中数据写入数据库
 {
     public partial class Form1 : Form
     {
         private SqlConnection myConnection = new SqlConnection();
         public Form1()
         {
             InitializeComponent();
         }

         private void Form1_Load(object sender, EventArgs e)
         {
             //定义字符串
             string connectionStr = "Server=localhost;integrated security=SSPI;Initial Catalog=mydb001";
             //创建连接对象
             myConnection = new SqlConnection(connectionStr);
             //测试是否连接成功
             try
             {
                 myConnection.Open();//打开数据库
             }
             catch
             {
                 MessageBox.Show("数据库连接错误","错误提示");
             }
             finally
             {
                 myConnection.Close();//关闭数据库
             }
             listGender.Items.Add("男");
             listGender.Items.Add("女");
             listGender.SelectedIndex = ;
             textName.Text = "";
             toolStripStatusLabel1.Text = "";
         }

         private void btnCreatData_Click(object sender, EventArgs e)
         {
             if (textName.Text.Trim() == "")
             {
                 MessageBox.Show("请输入姓名！","错误提示");
                 return;
             }
             int index = dataGridView1.Rows.Add();
             dataGridView1.Rows[index].Cells[].Value = textName.Text.Trim();
             dataGridView1.Rows[index].Cells[].Value = listGender.SelectedItem.ToString();
             dataGridView1.Rows[index].Cells[].Value = numAge.Value;
             toolStripStatusLabel1.Text = "向表格添加数据完成！";
         }

         private void btnSaveData_Click(object sender, EventArgs e)
         {
             bool result = true;
             try
             {
                 myConnection.Open();//打开数据库
                 for (int i = ; i < dataGridView1.RowCount; i++)
                 {
                     string commandSQLStr = "";//命令字符串
                     string commandSQLStr1 = "insert into mytable001(";//命令字符串
                     string commandSQLStr2 = ")values(";//命令字符串
                     string commandSQLStr3 = ")";//命令字符串
                     for (int j = ; j < dataGridView1.ColumnCount; j++)
                     {
                         if (j == )
                         {
                             commandSQLStr1 = commandSQLStr1 + dataGridView1.Columns[j].HeaderText.ToString();
                             if (dataGridView1.Rows[i].Cells[j].Value.GetType() == typeof(string))
                             {
                                 commandSQLStr2 = commandSQLStr2 +"\'"+ dataGridView1.Rows[i].Cells[j].Value.ToString() + "\'";
                             }
                             else
                             {
                                 commandSQLStr2 = commandSQLStr2 + dataGridView1.Rows[i].Cells[j].Value.ToString();
                             }
                         }
                         else
                         {
                             commandSQLStr1 = commandSQLStr1 + "," + dataGridView1.Columns[j].HeaderText.ToString();
                             if (dataGridView1.Rows[i].Cells[j].Value.GetType() == typeof(string))
                             {
                                 commandSQLStr2 = commandSQLStr2 + "," + "\'" + dataGridView1.Rows[i].Cells[j].Value.ToString() + "\'";
                             }
                             else
                             {
                                 commandSQLStr2 = commandSQLStr2 + "," + dataGridView1.Rows[i].Cells[j].Value.ToString();
                             }
                         }
                     }
                     commandSQLStr = commandSQLStr1 + commandSQLStr2 + commandSQLStr3;
                     SqlCommand myCommand = new SqlCommand(commandSQLStr, myConnection);//创建Command对象
                     myCommand.CommandTimeout = ;//设置超时时间为5秒
                     myCommand.ExecuteNonQuery();
                 }
             }
             catch
             {
                 result = false;
             }
             finally
             {
                 myConnection.Close();//关闭数据库
             }

             if (result)
             {
                 dataGridView1.Rows.Clear();
                 toolStripStatusLabel1.Text = "写入数据库成功！";
             }
             else
             {
                 toolStripStatusLabel1.Text = "写入数据库失败！";
             }
         }

         private void btnReadData_Click(object sender, EventArgs e)
         {
             try
             {
                 myConnection.Open();
                 string commandSQLStr = "select * from mytable001";//命令字符串
                 SqlCommand myCommand = new SqlCommand(commandSQLStr, myConnection);//创建Command对象
                 myCommand.CommandTimeout = ;//设置超时时间为5秒
                 SqlDataReader myDataReader = myCommand.ExecuteReader();
                 while (myDataReader.Read())
                 {
                     int index = dataGridView1.Rows.Add();
                     dataGridView1.Rows[index].Cells[].Value = myDataReader.GetValue();
                     dataGridView1.Rows[index].Cells[].Value = myDataReader.GetValue();
                     dataGridView1.Rows[index].Cells[].Value = myDataReader.GetValue();
                 }
                 myDataReader.Close();
                 toolStripStatusLabel1.Text = "从数据库读取数据完成！";
             }
             catch
             {
                 toolStripStatusLabel1.Text = "从数据库读取数据失败！";
             }
             finally
             {
                 myConnection.Close();
             }
         }
     }
 }