如何在gridview中显示前100个字符？

// 创建一个自定义的GridView列，用于显示前100个字符
public class GridViewColumn : ColumnBase
{
    public GridViewColumn()
    {
        this.Header = "前100个字符";
    }

    protected override FrameworkElement GenerateElement(DataGridCell cell, object dataItem)
    {
        var textBlock = new TextBlock();
        textBlock.TextTrimming = TextTrimming.CharacterEllipsis;
        textBlock.Text = GetFirst100Chars(dataItem);
        return textBlock;
    }

    private string GetFirst100Chars(object dataItem)
    {
        var text = dataItem.ToString();
        if (text.Length > 100)
        {
            return text.Substring(0, 100);
        }
        else
        {
            return text;
        }
    }
}

// 在GridView中使用自定义的GridView列
var gridView = new GridView();
var gridViewColumn = new GridViewColumn();
gridView.Columns.Add(gridViewColumn);