C#顯示基於組合框選擇的DataGridView

Question

我需要有關 C# windows 窗體應用程序的幫助。

我在表單中創建了一個 DataGridView，DataGridView 只需要根據用戶的組合框選擇顯示，組合框有三個選擇，每個選擇都需要顯示不同的數據庫表，例如，如果他們選擇了倉庫 1，則將顯示來自倉庫 1 數據庫。 如果他們選擇倉庫 2，那么將顯示數據庫表倉庫 2 和倉庫 3 的相同內容。

每個倉庫如果不同的數據庫。 到目前為止，我只在沒有組合框選擇的情況下添加倉庫 1 時就可以工作，但我需要基於組合框選擇。

創建到獲取數據庫表的每個函數后，將在每個數據庫的form1 方法中調用

這是我的代碼

 private void Form1_Load(object sender, EventArgs e)
        {

            // Bind the DataGridView to the BindingSource
            // and load the data from the database.

            if (cmb_DatabaseSelection.SelectedItem == "warehouse1")
            {
                dataGridView_ShowAllData.DataSource = bindingSource;

                GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
            }

            if (cmb_DatabaseSelection.SelectedItem == "warehouse2")
            {
                dataGridView_ShowAllData.DataSource = bindingSource;

                GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
            }

            if (cmb_DatabaseSelection.SelectedItem == "warehouse3")
            {
                dataGridView_ShowAllData.DataSource = bindingSource;

                GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
            }



            this.rpt_CallSSRSReport.RefreshReport();

            CallReport();
        }


private void GetLeMarsConnectionDatabaseConnection(string selectCommand)
        {


            try
            {

                //Create the connection string, data adapter and data table.
                String connectionString = "database1";


                // Specify a connection string. Replace the given value with a 
                // database accessible to your system.

                // Create a new data adapter based on the specified query.
                dataAdapter = new SqlDataAdapter(selectCommand, connectionString);

                // Create a command builder to generate SQL update, insert, and
                // delete commands based on selectCommand. These are used to
                // update the database.
                SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);

                // Populate a new data table and bind it to the BindingSource.
                System.Data.DataTable table = new System.Data.DataTable();
                table.Locale = System.Globalization.CultureInfo.InvariantCulture;
                dataAdapter.Fill(table);
                bindingSource.DataSource = table;

                // Resize the DataGridView columns to fit the newly loaded content.
                dataGridView_ShowAllData.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);

            }
            catch (SqlException)
            {
                MessageBox.Show("Database connection ERROR");
            }

        }

        private void GetSchuylerConnectionDatabaseConnection(string selectCommand)
        {
            try
            {

                //Create the connection string, data adapter and data table.
                String connectionString = "database2";


                // Specify a connection string. Replace the given value with a 
                // database accessible to your system.

                // Create a new data adapter based on the specified query.
                dataAdapter = new SqlDataAdapter(selectCommand, connectionString);

                // Create a command builder to generate SQL update, insert, and
                // delete commands based on selectCommand. These are used to
                // update the database.
                SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);

                // Populate a new data table and bind it to the BindingSource.
                System.Data.DataTable table = new System.Data.DataTable();
                table.Locale = System.Globalization.CultureInfo.InvariantCulture;
                dataAdapter.Fill(table);
                bindingSource.DataSource = table;

                // Resize the DataGridView columns to fit the newly loaded content.
                dataGridView_ShowAllData.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);

            }
            catch (SqlException)
            {
                MessageBox.Show("Database connection ERROR");
            }

        }

        private void GetDetroitLakesConnectionDatabaseConnection(string selectCommand)
        {
            try
            {

                //Create the connection string, data adapter and data table.
                String connectionString = "database3";


                // Specify a connection string. Replace the given value with a 

                // database accessible to your system.

                // Create a new data adapter based on the specified query.
                dataAdapter = new SqlDataAdapter(selectCommand, connectionString);

                // Create a command builder to generate SQL update, insert, and
                // delete commands based on selectCommand. These are used to
                // update the database.
                SqlCommandBuilder commandBuilder = new SqlCommandBuilder(dataAdapter);

                // Populate a new data table and bind it to the BindingSource.
                System.Data.DataTable table = new System.Data.DataTable();
                table.Locale = System.Globalization.CultureInfo.InvariantCulture;
                dataAdapter.Fill(table);
                bindingSource.DataSource = table;

                // Resize the DataGridView columns to fit the newly loaded content.
                dataGridView_ShowAllData.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);

            }
            catch (SqlException)
            {
                MessageBox.Show("Database connection ERROR");
            }

        }

Answer 1

(1) 雙擊組合框。 下面的代碼會出現在你的代碼后面

    private void cmb_DatabaseSelection_SelectedIndexChanged(object sender, EventArgs e)
    {

    }

或者你也可以添加這樣的事件

將以下代碼添加到上述函數中（根據您的需要編寫代碼）

if (cmb_DatabaseSelection.SelectedItem == "warehouse1")
        {
            dataGridView_ShowAllData.DataSource = bindingSource;

            GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
        }

        if (cmb_DatabaseSelection.SelectedItem == "warehouse2")
        {
            dataGridView_ShowAllData.DataSource = bindingSource;

            GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
        }

        if (cmb_DatabaseSelection.SelectedItem == "warehouse3")
        {
            dataGridView_ShowAllData.DataSource = bindingSource;

            GetLeMarsConnectionDatabaseConnection("Select * from dbo.AllInvoicesInReadyStatus");
        }