Inserting Data into a Table Using C# Windows Forms Application

In this article, we will discuss how to insert data into a table using a C# Windows Forms application. We will go through the steps of creating a connection string, opening a database connection, and executing SQL commands.

Understanding the Basics

Before we dive into the code, it’s essential to understand the basics of the technology involved:

Connection Strings

A connection string is a piece of text that identifies a data source and specifies the protocol to use when connecting to it. In this case, we will be using a SQL Server connection string.

SQL Commands

SQL (Structured Query Language) is a language used to manage relational databases. SQL commands are used to perform various operations on data in the database, such as inserting, updating, or deleting data.

Creating a Connection String

The first step in connecting to a database is to create a connection string. A connection string typically includes the following components:

The data source (e.g., server name, database name)
The protocol used to connect to the data source (e.g., SQL Server)
The username and password for authentication
Other settings specific to the data source

In our example, we will be using a pre-configured connection string provided by the application’s properties settings.

Creating a Database Connection

Once we have created a connection string, we can use it to establish a database connection. This involves creating a new instance of the SqlConnection class and passing the connection string to its constructor.

// Create a new instance of SqlConnection
SqlConnection sqlConnection = new SqlConnection(con_string);

// Open the database connection
sqlConnection.Open();

Executing SQL Commands

To execute an SQL command, we need to create a new instance of the SqlCommand class and pass the SQL command as a string to its constructor. We can then add parameters to the command using the AddWithValue method.

// Create a new instance of SqlCommand
SqlCommand mycom = new SqlCommand(myinsert, sqlConnection);

// Add parameters to the command
mycom.Parameters.AddWithValue("@Titel", textBox1.Text);
mycom.Parameters.AddWithValue("@Inerpret", textBox2.Text);

// Execute the SQL command
sqlConnection.Open();
mycom.ExecuteNonQuery();

Handling Errors

When working with database connections and SQL commands, it’s essential to handle errors that may occur during execution. We can use a try-catch block to catch any exceptions that are thrown.

try
{
    sqlConnection.Open();
    mycom.ExecuteNonQuery();
}
catch (SqlException ex)
{
    // Handle the error
    MessageBox.Show(ex.Message);
}

Show Results

After executing the SQL command, we need to show the results. We can do this by retrieving the data from the database using a DataTable or a DataGridView.

// Create a new instance of SqlDataAdapter
SqlDataAdapter da = new SqlDataAdapter(myselect, sqlConnection);

// Fill the DataTable with data
da.Fill(dt);

// Set the DataSource property of the DataGridView to the DataTable
dataGridView1.DataSource = dt;

Example Use Case

Here’s an example use case that demonstrates how to insert data into a table using C# Windows Forms application:

private void btnAdd_Click(object sender, EventArgs e)
{
    // Create a new instance of SqlConnection
    string con_string = "database connection string";
    SqlConnection sqlConnection = new SqlConnection(con_string);

    // Create the SQL command
    string myinsert = "insert into tab_Musik values (@Titel,@Inerpret)";
    SqlCommand mycom = new SqlCommand(myinsert, sqlConnection);

    // Add parameters to the command
    mycom.Parameters.AddWithValue("@Titel", textBox1.Text);
    mycom.Parameters.AddWithValue("@Inerpret", textBox2.Text);

    try
    {
        // Open the database connection
        sqlConnection.Open();

        // Execute the SQL command
        mycom.ExecuteNonQuery();
    }
    catch (SqlException ex)
    {
        // Handle the error
        MessageBox.Show(ex.Message);
    }

    // Clone and dispose of the SqlCommand object
    mycom.Clone();
    mycom.Dispose();
}

This example demonstrates how to create a connection string, establish a database connection, execute an SQL command, and handle errors.

Conclusion

In this article, we discussed how to insert data into a table using C# Windows Forms application. We covered the basics of creating a connection string, opening a database connection, executing SQL commands, handling errors, and showing results. With this knowledge, you should be able to create your own C# Windows Forms applications that interact with databases.

Additional Resources

By following the steps outlined in this article, you should be able to create a C# Windows Forms application that inserts data into a table. Remember to always handle errors and show results to ensure that your application provides a good user experience.

Troubleshooting Tips

Make sure to check the connection string for any typos or errors.
Verify that the database server is running and accepting connections.
Check for any SQL syntax errors in the command being executed.
Make sure to handle any exceptions that may occur during execution.

Last modified on 2025-04-23