Python pickle 模块提供了把对象序列化的方法，对象会被序列化成ASCII的字符串，可以保存到文件。unpickle则可以从文件或字符中反序列化成对象。如下的两个方法非常有用。
- pickle. dumps ( obj[, protocol] )
-
Return the pickled representation of the object as a string, instead of writing it to a file.
If the protocol parameter is omitted, protocol 0 is used. If protocol is specified as a negative value or HIGHEST_PROTOCOL, the highest protocol version will be used.
Changed in version 2.3: The protocol parameter was added.
- pickle. loads ( string )
- Read a pickled object hierarchy from a string. Characters in the string past the pickled object’s representation are ignored.
我在使用wx时，wxGrid的GetCellValue方法只能返回字符串。但我希望它可以返回我定义的对象，于是我找到了pickle。我在类中重写__str__()方法，使用pickle来序列化这个对象。
例子：
import pickle
class LineProperty:
def __init__(self, width=0, shape=0xFFFF, r=0, g=0, b=0, color=0):
self.width = width
self.shape = shape
self.r = r
self.g = g
self.b = b
self.color = color
#使用pickle 序列化
def __str__(self):
return pickle.dumps(self)
然后我在自己定义的wxGridTable中设置了这个数据，GridCellEditor中的重写的
BeginEditor方法
class LineGridCellEditor(grd.PyGridCellEditor):
def Create(self, parent, id, evtHandler):
self._control = wx.Control(parent, id, wx.DefaultPosition, (100, 100))
self._parent = parent
self.SetControl(self._control)
newEvt = wx._core.EvtHandler()
if newEvt:
self._control.PushEventHandler(newEvt)
self.startValue = self.endValue = None
self.m_canvas = linecanvas.MyLineCanvas(self._control)
def OnClick(self, evt):
pass
def Clone(self):
return LineGridCellEditor()
def BeginEdit(self, row, col, grid):
self.startValue = grid.GetCellValue(row, col)
#在这里反序列化，传递给canvas
self.m_canvas.SetScales(pickle.loads(str(self.startValue)))
这样就可以摆脱GetCellValue只能返回wxString的限制了。把对象传输过来，用glCanvas来绘制。
