Understanding Data from Textbox to Datagrid Databinding

As a developer, we often encounter scenarios where we need to bind data from textboxes to datagrids. This process involves retrieving data from user input and displaying it in a datagrid. In this article, we will delve into the world of databinding and explore how to achieve this feat.

Introduction to Databinding

Databinding is a process that enables us to connect our applications to external data sources, such as databases or file systems. This connection allows us to display data in our application’s user interface. In this case, we will focus on binding textboxes to datagrids using databinding.

The Problem: Hidden Columns and Autonumber

The provided Stack Overflow question highlights a common issue when working with datagrids and textboxes. The problem arises when we have multiple columns in the datagrid, including hidden columns (e.g., autonumber), and we want to bind data from textboxes to these columns.

In the example code, we see that the developer has added a binding source (bsData) to hold the data for the datagrid. The binding source is then connected to a DataTable object (dtr). However, when working with relationship tables (i.e., tables with foreign keys), the hidden columns (e.g., autonumber) are not visible in the datagrid.

To resolve this issue, we need to understand how to work with hidden columns and autonumber values. In the provided code snippet, the developer has used MappingType.Hidden when adding a new column to the DataTable. This tells Visual Studio to hide the column from the user interface, but still allows us to access it programmatically.

Understanding Mapping Types

In .NET, there are several mapping types that we can use when binding data to a datagrid. These mapping types determine how the data is displayed and how it is accessed programmatically.

Here’s a brief overview of the most commonly used mapping types:

• MappingType.Hidden: This mapping type hides the column from the user interface.
• MappingType.Visible: This mapping type displays the column in the user interface.
• MappingType.Bound: This mapping type binds the column to a specific data source (e.g., a textbox).

By using MappingType.Hidden, we can ensure that our hidden columns (e.g., autonumber) are still accessible programmatically.

Creating a Binding Source

To create a binding source, we need to follow these steps:

1. Create a new instance of the BindingSource class.
2. Set the data source for the binding source to a DataTable, DataSet, or another data source object.
3. Configure any additional settings (e.g., filtering, sorting) as needed.

Here’s an updated code snippet that demonstrates how to create a binding source:

{< highlight csharp >}
using System.Windows.Forms;

// Create a new instance of the BindingSource class
public BindingSource bsData = new BindingSource();

// Set the data source for the binding source
DataTable dtr = new DataTable();
dtr.Columns.Add(new DataColumn("hiddenid", typeof(Integer)));
dtr.Columns.Add(new DataColumn("autonumber", typeof(String)));
dtr.Columns.Add(new DataColumn("location", typeof(String)));
dtr.Columns.Add(new DataColumn("date", typeof(String)));

// Set the data source for the binding source
bsData.DataSource = dtr;

// Configure any additional settings as needed (e.g., filtering, sorting)
// ...
{/ highlight }

Binding Textboxes to Datagrids

To bind textboxes to datagrids, we need to follow these steps:

1. Create a new instance of the DataGridView class.
2. Set the data source for the datagrid to a BindingSource object (e.g., bsData).
3. Configure any additional settings (e.g., column widths, formatting) as needed.

Here’s an updated code snippet that demonstrates how to bind textboxes to datagrids:

{< highlight csharp >}
using System.Windows.Forms;

// Create a new instance of the DataGridView class
NDRDataGridView = new DataGridView();

// Set the data source for the datagrid
bsData.DataSource = NDRDataGridView;

// Configure any additional settings as needed (e.g., column widths, formatting)
NDRDataGridView.Columns.Add("hiddenid", typeof(Integer));
NDRDataGridView.Columns.Add("autonumber", typeof(String));
NDRDataGridView.Columns.Add("location", typeof(String));
NDRDataGridView.Columns.Add("date", typeof(String));

// ...
{/ highlight }

Handling Enter Key Presses

To handle enter key presses and add data to the datagrid, we can use the following code snippet:

{< highlight csharp >}
using System.Windows.Forms;

// ...

If e.KeyChar = Microsoft.VisualBasic.ChrW(Keys.Return) Then

    If Not String.IsNullOrWhiteSpace(HiddenidTextBox.Text) Then
        // Add data to the datagrid
        DataTable dtr = (DataTable)bsData.DataSource;
        dtr.Rows.Add(null, HiddenidTextBox.Text, LocationTextBox.Text, DateTextBox1.Text);
        
        // Move to the last row in the datagrid
        bsData.MoveLast();
    End If

End If
{/ highlight }

Conclusion

In this article, we explored how to bind data from textboxes to datagrids using databinding. We discussed the importance of understanding mapping types and creating binding sources. We also provided code snippets that demonstrate how to create a binding source and bind textboxes to datagrids.

By following these steps and examples, you should be able to achieve successful databinding between your application’s user interface and external data sources.

Last modified on 2025-03-08