public override void InitializeEditingControl(int rowIndex, object
initialFormattedValue, DataGridViewCellStyle dataGridViewCellStyle)
{
this._oldValue = this.Value;
this._oldValueInitialize = true;
base.InitializeEditingControl(rowIndex, initialFormattedValue,
dataGridViewCellStyle);
ComboBoxCellEditingControl ctl =
DataGridView.EditingControl as ComboBoxCellEditingControl;
ctl.PropertyGirdAttribute = this._propertyRelatorAttribute;
PropertyComboBoxEditorAttribute editorAttribute = (PropertyComboBoxEditorAttribute)this.PropertyEditorAttribute;
ctl.DataSource = EnumDescConverter.Get(editorAttribute.Enum);
if (this.Value != null)
{
ctl.SelectedValue = this.Value.ToString();
}
else
{
ctl.SelectedValue = String.Empty;
}
}
protected override object GetFormattedValue(object value, int rowIndex, ref DataGridViewCellStyle cellStyle,
System.ComponentModel.TypeConverter valueTypeConverter, System.ComponentModel.TypeConverter formattedValueTypeConverter,
DataGridViewDataErrorContexts context)
{
string strValue = String.Empty;
if (value != null)
{
PropertyComboBoxEditorAttribute editorAttribute = (PropertyComboBoxEditorAttribute)this.PropertyEditorAttribute;
if (editorAttribute != null)
{
DataRow[] dr = EnumDescConverter.Get(editorAttribute.Enum).Select("Value='" + value + "'");
if (dr.Length > 0)
{
strValue = dr[0]["Text"].ToString();
}
}
else
{
strValue = value.ToString();
}
}
return(base.GetFormattedValue(strValue, rowIndex, ref cellStyle, valueTypeConverter, formattedValueTypeConverter, context));
}
/// <summary>
/// 将当前属性值与默认属性值（如果有）对比
/// 如果不同，就把当前属性值粗体显示，否则常规显示
/// </summary>
internal void ContrastDefaultValue()
{
if (this.DataGridView == null)
{
return;
}
//如果是只读，直接默认字体就行了，没必要加粗显示，也就没必要比较值
if (this.ReadOnly)
{
_propertyGridCell.Style.Font = this.DataGridView.DefaultCellStyle.Font;
return;
}
object objCurrentValue = GetPropertyValue();
if (objCurrentValue == null)
{
return;
}
//这里必须判断当前值是否是空串，如果是空串，在下面进行类型转换时肯定会异常
//如尝试把空串转成Int
if (objCurrentValue.ToString() == String.Empty)
{
return;
}
if (_iPropertyGirdCell.DefaultValueAttribute == null)
{
return;
}
bool equal = true;
if (_iPropertyGirdCell.DefaultValueAttribute.Value.GetType().IsEnum)
{
PropertyComboBoxEditorAttribute editorAttribute = (PropertyComboBoxEditorAttribute)_iPropertyGirdCell.PropertyEditorAttribute;
equal = Enum.Parse(editorAttribute.Enum, objCurrentValue.ToString()).Equals(_iPropertyGirdCell.DefaultValueAttribute.Value);
}
else
{
//设置过来的值是String，如 "300"，而默认值是Property的类型，如Int
//在这种情况下需要类型转换后再做比较判断，否则结果永远是false
if (Type.Equals(objCurrentValue, _iPropertyGirdCell.DefaultValueAttribute.Value))
{
equal = objCurrentValue.Equals(_iPropertyGirdCell.DefaultValueAttribute.Value);
}
else
{
IConvertible convertible = objCurrentValue as IConvertible;
if (convertible != null)
{
equal = Convert.ChangeType(
objCurrentValue, _iPropertyGirdCell.DefaultValueAttribute.Value.GetType()
).Equals(_iPropertyGirdCell.DefaultValueAttribute.Value);
}
else
{
equal = objCurrentValue.Equals(_iPropertyGirdCell.DefaultValueAttribute.Value);
}
}
}
if (equal)
{
_propertyGridCell.Style.Font = this.DataGridView.DefaultCellStyle.Font;
}
else
{
_propertyGridCell.Style.Font = new Font(this.DataGridView.DefaultCellStyle.Font, FontStyle.Bold);
}
}
