![]() ![]() ![]() ![]() Storing sensitive information, such as a password, within the connection string can affect the security of your application. Be sure that you set the connectionString variable to a value that is appropriate for your database. This code example uses a GetData method that returns a populated DataTable object. Implement a method in your form's class definition for handling the details of connecting to the database. Me.Text = "DataGridView validation demo (disallows empty CompanyName)" Private bindingSource1 As New BindingSource() Private WithEvents dataGridView1 As New DataGridView() This.Text = "DataGridView validation demo (disallows empty CompanyName)" This.Load += new EventHandler(Form1_Load) Private BindingSource bindingSource1 = new BindingSource() Private DataGridView dataGridView1 = new DataGridView() The following code example provides basic initialization and includes a Main method. Access to a server that has the Northwind SQL Server sample database.Ĭreating the Form To validate data entered in a DataGridViewĬreate a class that derives from Form and contains a DataGridView control and a BindingSource component.In order to complete this walkthrough, you will need: To copy the code in this topic as a single listing, see How to: Validate Data in the Windows Forms DataGridView Control. When a user edits a cell in the CompanyName column and tries to leave the cell, the CellValidating event handler will examine new company name string to make sure it is not empty if the new value is an empty string, the DataGridView will prevent the user's cursor from leaving the cell until a non-empty string is entered. In this walkthrough, you will retrieve rows from the Customers table in the Northwind sample database and display them in a DataGridView control. You can validate data by handling the CellValidating event, which is raised by the DataGridView when the current cell changes. The DataGridView class provides a convenient way to perform validation before data is committed to the data store. It wouldn't necessarily be any more efficient, but it would make the controls less intimidating and allow for larger click targets through better space distribution.When you display data entry functionality to users, you frequently have to validate the data entered into your form. If #3 is false, you might be able to break the table down into smaller, logical groups. The header could be 2-28, where the cells below represent duplicative data across columns and an expand link allows the user to change individual cells. In the context of a table, think of how you might hide columns in a spreadsheet and only expand when you need to inspect detail. If #2 is false, you can probably compress the table in a way that is both helpful to the user and improves use of screen real estate. Without understanding the workflow and meaning of the data, it's very hard to say what that presentation might be. If #1 is false, you can start considering other presentations. Is the continuous progression of the data set from one cell to the next important? If not, it may be possible to break the whole array into groups.Is the discrete value of each cell important, or do users tend to deal with them in bulk? I ask because your example has only a small number of deviations. ![]() Is the position of a cell meaningful to the user? If it's important that they understand how a unit relates to two relational axes, the grid presentation is probably the most efficient option.But I'll pose a few questions just the same. Wow! That's an impressive settings table! Even a little scary.įrom the looks of it, I'm assuming this is a proprietary app you can't tell us too much about. ![]()
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