datagridview column width autosize code example
Example: datagridview c# resize columns
private void Form1_Load(object sender, System.EventArgs e)
{
// Bind the DataGridView controls to the BindingSource
// components and load the data from the database.
masterDataGridView.DataSource = masterBindingSource;
detailsDataGridView.DataSource = detailsBindingSource;
GetData();
// Resize the master DataGridView columns to fit the newly loaded data.
masterDataGridView.AutoResizeColumns();
// Configure the details DataGridView so that its columns automatically
// adjust their widths when the data changes.
detailsDataGridView.AutoSizeColumnsMode =
DataGridViewAutoSizeColumnsMode.AllCells;
}