WPF,DataGrid Cell TextWrapping Programmatically

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C#

WPF

DataGrid

I used DataGrid Control in my App. since I am new at WPF, there is always somestuff I don't understand. I want to each cell in DataGrid show Multi line text when dispalying Text is so much. I tried to find out solution and Tried some codes , but did not make it out.
I find a way for make cell border red when it is editing. code as blow

//Cell border turn red when editing
 Style cellStyle = new Style(typeof(DataGridCell));
 Trigger isEditingTrigger = new Trigger();
 isEditingTrigger.Property = DataGridCell.IsEditingProperty;
 isEditingTrigger.Value = true;
 isEditingTrigger.Setters.Add(new Setter(DataGridCell.BorderBrushProperty, Brushes.Red));
 cellStyle.Triggers.Add(isEditingTrigger);

 // Set the cell style for the grid
 this.m_DataGrid.CellStyle = cellStyle;

I tried to use similar methods, but failed. How can I set TextWrapping property for Multi line text Display.

I did not put any control in my DataGrid cell, so how can I make it display multi line text programmatically ? Please note, I need Programmatic method.

please help!