如何在数据集中插入新的datagridview行并在数据库中更新？ [英] How to insert new datagridview row in dataset and update in database?

问题描述

所有



我开始用C＃编程。我有问题：我创建了项目表，其中包含2行，编程为

Hi, all

I started programming in C#. I have problem: I created "Projects" table with 2 rows which are programmed in

get; set; 

class：ID，PROJECTS_NAME。我已经完成了在此表中编辑值：

class: ID, PROJECTS_NAME. I have already done with editing values in this table:

private void dataGridView4_CellEndEdit(object sender, DataGridViewCellEventArgs e)
       {
           string name_project = dataGridView4.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString();
           string id = dataGridView4.Rows[e.RowIndex].Cells[0].Value.ToString();

           MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
           MySqlCommand cmd = new MySqlCommand("UPDATE projekt1.projects SET PROJECTS_NAME = @PROJECTS_NAME WHERE ID = @ID", connection);

           cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = int.Parse(id);
           cmd.Parameters.Add("@PROJECTS_NAME", MySqlDbType.VarChar).Value = name_project;

           try
           {
               connection.Open();
               cmd.ExecuteNonQuery();
               connection.Close();
           }
           catch (Exception ex)
           {
               MessageBox.Show(ex.Message);
           }
       }

项目中的SQL列表：

SQL Columns in projects Table:

PROJECT_NAME VARCHAR
ID INT

它运行正常。但我在插入新行并自动保存在数据库中时遇到问题。



我尝试过：



我尝试过RowValidated事件：

And it works fine. But i have a problem with inserting new row and saving automatically in database.

What I have tried:

I've tried with RowValidated Event:

private void dataGridView4_RowValidated(object sender, DataGridViewCellEventArgs e)
     {
         string name_project = dataGridView4.Rows[e.RowIndex].Cells[1].Value.ToString();
         string id = dataGridView4.Rows[e.RowIndex].Cells[0].Value.ToString();

         MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
         MySqlCommand cmd = new MySqlCommand("INSERT INTO projekt1.projects(PROJECT_NAME) VALUES(@NPROJECT_NAME);", connection);

         cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = int.Parse(id);
         cmd.Parameters.Add("@PROJECT_NAME", MySqlDbType.VarChar).Value = name_project;

         try
         {
             connection.Open();
             cmd.ExecuteNonQuery();
             connection.Close();

             MessageBox.Show("ok");
         }
         catch (Exception ex)
         {
             MessageBox.Show(ex.Message);
         }

         try
         {
             connection.Open();
             cmd.ExecuteNonQuery();
             connection.Close();
         }
         catch (Exception ex)
         {
             MessageBox.Show(ex.Message);
         }

但由于

But it didn't work because of

System.FormatException: "Invalid input string format."

有人可以解释一下如何解决它吗？我搜索了一些东西，但我不知道如何处理。问候语

Can someone please explain how to solve it? I've searched something but i don't know how to deal with. Greetings

推荐答案

你必须使用

UserAddedRow

投入

RowValidated

 private void dataGridView4_UserAddedRow(object sender, DataGridViewRowEventArgs e)
     {
         string name_project = e.Row.Cells.Cells[1].Value.ToString();
         int id = Convert.ToInt64(e.Row.Cells[0].Value.ToString());

         MySqlConnection connection = new MySqlConnection("datasource = localhost; port = 3306; username = root; password = ");
         MySqlCommand cmd = new MySqlCommand("INSERT INTO projekt1.projects(PROJECT_NAME) VALUES(@NPROJECT_NAME);", connection);

         cmd.Parameters.Add("@ID", MySqlDbType.Int64).Value = id;
         cmd.Parameters.Add("@PROJECT_NAME", MySqlDbType.VarChar).Value = name_project;

         try
         {
             connection.Open();
             cmd.ExecuteNonQuery();
             connection.Close();

             MessageBox.Show("ok");
         }
         catch (Exception ex)
         {
             MessageBox.Show(ex.Message);
      }   
}

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