E2031 Cannot cast from 'TComponent *' to 'TColumn *'

[robin_wan]

void __fastcall TfrmMain::btnClick(TObject *Sender)
{
TComponent *frmComponent;
TIniFile *ini;
ini = new TIniFile( "abc.ini" );
try
{
for(int i=0 ;i<ComponentCount;i++) //遍历Form组件
{
frmComponent=Components[i];
if (frmComponent->ClassNameIs("TColumn") )
{
dynamic_cast<TColumn *>(frmComponent)->Title->Caption=
ini->ReadString(pFrom->Name,frmComponent->Name
+".Title.Caption",dynamic_cast<TColumn *>(frmComponent)->Title->Caption);
}
}
}
__finally
{
delete ini;
}
类型转换出错，请问如何处理???
[C++ Error] utLanguage.cpp(149): E2031 Cannot cast from 'TComponent *' to 'TColumn *'

[[e-mail]]

TObject->TPersistent->TCollectionItem->TColumn
你遍歷Form的組建是抓不到Colum的

[yuanreid]

TColumn类并非继承自TCompoent，因此通过ComponentCount无法遍历

[robin_wan]

查看了一下帮助，遍歷Form的組建是抓不到Colum的。
哪么我要能够遍历Form上的组件要怎样做呢？

[jxw1987628]

不是所有的组件都包含像TColumn这样的对象，

有的控件才有，如TListView 应该有TCollection

TDBGrid应该有TColumn。。

[sczyq]

是一个语言转换文件吧，我就是这样做的！

if (Control->ClassNameIs("TDBGrid"))
// func params:  (TControl *Control, TIniFile *IniFile, AnsiString ASection)

{
	TDBGrid *DBGrid= (TDBGrid *)Control;
	TColumn *Column;
	AnsiString ColumnFieldName;
	for (int i=0; i<DBGrid->Columns->Count; i++)
	{
		Column = DBGrid->Columns->Items[i];
		ColumnFieldName = Column->FieldName;
		if (ColumnFieldName.Length())
			Column->Title->Caption = IniFile->ReadString(ASection,
				DBGrid->Name + "." + ColumnFieldName,
				Column->Title->Caption);
	}
}