How do I test a DataGridView cell to see if font style is bold?

Question

Hi all,

I am traversing through the cells in a DataGridView row to print them. I need to determine whether the font style in the cell is bold. How can I do this?

The code follows:

foreach (DataGridViewCell Cel in GridRow.Cells)
   {
      if (Cel.Value != null)
        {

           //This is always false.
           if (Cel.InheritedStyle.Font.Bold)
               fontPrint = fontPrintBold;
           else
               fontPrint = new Font("Ariel", 11, FontStyle.Regular);

           e.Graphics.DrawString(Cel.Value.ToString(),
               //Cel.InheritedStyle.Font,
               fontPrint,
               new SolidBrush(Cel.InheritedStyle.ForeColor),
               new RectangleF((int)arrColumnLefts[iCount],
               (float)iTopMargin,
               (int)arrColumnWidths[iCount], (float)iCellHeight),
               strFormat);
        }

      iCount++;
   }

I also tried using

Cel.Style.Font.Bold

However, this gives a null reference exception. I am trying to print bold font whenever the text in the cell is bold.

Any orientation is appreciated. Thank you, Saga

Answer 1

See if you can adapt the following to your task. Currently it's checking column index 0 but you can modify to do all cells.

using System;  
using System.Reflection;  
using System.Windows.Forms;  
  
namespace WindowsFormsSample  
{  
    public static class DataGridViewColumnExtensions  
    {  
        public static DataGridViewCellStyle GetFormattedStyle(this DataGridViewCell cell)  
        {  
            var dgv = cell.DataGridView;  
  
            if (dgv == null)  
            {  
                return cell.InheritedStyle;  
            }  
  
            var formattingArgs = new DataGridViewCellFormattingEventArgs(  
                cell.ColumnIndex,   
                cell.RowIndex,   
                cell.Value,   
                cell.FormattedValueType,   
                cell.InheritedStyle);  
  
            var methodInfo = dgv.GetType().GetMethod("OnCellFormatting",  
                BindingFlags.Instance | BindingFlags.NonPublic,  
                null,  
                new Type[] { typeof(DataGridViewCellFormattingEventArgs) },  
                null);  
  
            methodInfo.Invoke(dgv, new object[] { formattingArgs });  
            return formattingArgs.CellStyle;  
        }  
    }  
}  

Form code, the column is defined in the designer.

using System;  
using System.Drawing;  
using System.Windows.Forms;  
  
namespace WindowsFormsSample  
{  
    public partial class Form1 : Form  
    {  
        public Form1()  
        {  
            InitializeComponent();  
  
            dataGridView1.CellFormatting += DataGridView1OnCellFormatting;  
        }  
  
        private void DataGridView1OnCellFormatting(object sender, DataGridViewCellFormattingEventArgs e)  
        {  
            if (e.ColumnIndex != 0) return;  
  
            if (Convert.ToString(dataGridView1.Rows[e.RowIndex].Cells[0].Value) == "Anne")  
            {  
                dataGridView1.Rows[e.RowIndex].DefaultCellStyle.BackColor = Color.DarkSalmon;  
                e.CellStyle.Font = new Font(e.CellStyle.Font, FontStyle.Bold);  
            }  
            else  
            {  
                dataGridView1.Rows[e.RowIndex].DefaultCellStyle.BackColor = Color.Empty;  
                e.CellStyle.Font = new Font(e.CellStyle.Font, FontStyle.Regular);  
            }  
        }  
          
        private void Form1_Load(object sender, EventArgs e)  
        {  
            dataGridView1.Rows.Add("Karen");  
            dataGridView1.Rows.Add("Anne");  
            dataGridView1.Rows.Add("Karen");  
            dataGridView1.Rows.Add("Anne");  
            dataGridView1.Rows.Add("Mary");  
            dataGridView1.Rows.Add("Anne");  
        }  
  
        private void IterateRowsButton_Click(object sender, EventArgs e)  
        {  
              
            listBox1.Items.Clear();  
  
            for (int index = 0; index < dataGridView1.Rows.Count -1; index++)  
            {  
                  
                if (dataGridView1.Rows[index].IsNewRow)  
                {  
                    continue;  
                }  
  
                var cellStyle = dataGridView1.Rows[index].Cells[0].GetFormattedStyle();  
                listBox1.Items.Add(cellStyle.Font.Bold ? $"{index} is bold" : $"{index} is not bold");  
            }  
              
        }  
    }  
}  
  

Answer 2

I'm not sure if this work, but if you verify that your Class starts with something like this:
Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
Inherits System.Windows.Forms.Form
Private WithEvents dvgData As New DataGridView
.....

Then something like:
Private Sub dvgData_CellFormatting(ByVal sender As Object, _
ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) _
Handles dvgData.CellFormatting

.....

If you want to change the font in a whole column, you could try something like this:
With dvgData
.Name = "dvgData"
.Columns(0).DefaultCellStyle.Font = _
New Font(dvgData.DefaultCellStyle.Font, FontStyle.Bold)
.....

A few last words...
I think the best stable solution is to create a new Font instance, specifically directed to the column, row or cell you whish to change.