Question

tooltips for datagrid?

Asked by: pillmill

Tried to use the attached MS code to create tooltips
for the cells of a datagrid. Got this unhandled exception.
How can I fix this?

Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object.
   at tooltip3.Form1.dataGridView1_CellFormatting(Object sender, DataGridViewCellFormattingEventArgs e) in C:\Documents and Settings\millerph\My Documents\Visual Studio 2008\Projects\tooltip\tooltip3\tooltip3\Form1.cs:line 17
   at System.Windows.Forms.DataGridView.OnCellFormatting(DataGridViewCellFormattingEventArgs e)
   at System.Windows.Forms.DataGridView.OnCellFormatting(Int32 columnIndex, Int32 rowIndex, Object val, Type formattedValueType, DataGridViewCellStyle cellStyle)
   at System.Windows.Forms.DataGridViewCell.GetFormattedValue(Object value, Int32 rowIndex, DataGridViewCellStyle& cellStyle, TypeConverter valueTypeConverter, TypeConverter formattedValueTypeConverter, DataGridViewDataErrorContexts context)


void dataGridView1_CellFormatting(object sender, 
    DataGridViewCellFormattingEventArgs e)
{
    if ( (e.ColumnIndex == this.dataGridView1.Columns["Rating"].Index)
        && e.Value != null )
    {
        DataGridViewCell cell = 
            this.dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];
        if (e.Value.Equals("*"))
        {                
            cell.ToolTipText = "very bad";
        }
        else if (e.Value.Equals("**"))
        {
            cell.ToolTipText = "bad";
        }
        else if (e.Value.Equals("***"))
        {
            cell.ToolTipText = "good";
        }
        else if (e.Value.Equals("****"))
        {
            cell.ToolTipText = "very good";
        }
    }
}
                                  
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Asked On
2009-11-05 at 09:03:18ID24875136
Topics

C# Programming Language

,

Microsoft Visual C#.Net

,

.NET Framework 3.x versions

Participating Experts
1
Points
500
Comments
1

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Answers

 

by: five22bagsPosted on 2009-11-05 at 09:40:30ID: 25751901

Where is it erroring on you? is it  e.Value is null? is cell null?

20120131-EE-VQP-002

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