I am trying to programmatically remove a selected component from its parent container using the code below (I may be using found incorrectly, but that is not the problem, suggestions are welcome):
void __fastcall TScrollControlsListContainer::RemoveItem(TWinControl* ctrl)
{
// find control in vector containing TWinControl(s)
std::vector<FWinControl*>::iterator found = std::find_if(FWinControls.begin(), FWinControls.end(), IsCtrl(ctrl));
if(found != FWinControls.end())
{
Components->RemoveComponent(dynamic_cast<TComponent*>(found));
//[bcc32 Error] ScrollControlsListContainer.cpp(208): E2193 Too few parameters in call to '_fastcall TComponent::GetComponent(int)' Full parser context
FWinControls.erase(found);
}
}
I am confused about the error, as only one parameter is required according to the help file example below:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int I;
TComponent *Temp;
Memo1->Lines->Add("Components removed: ");
Form2->Memo1->Lines->Add("Components added: ");
for (I = ComponentCount - 1; I >= 0; I--)
{
Temp = Components[I];
// Move only the components that are not controls.
if (dynamic_cast<TControl *>(Temp) == NULL)
{
RemoveComponent(Temp);
Memo1->Lines->Add(Temp->Name);
Form2->InsertComponent(Temp);
Form2->Memo1->Lines->Add(Temp->Name);
}
}
}
What am I missing here?
Related
I have semi-successfully translated reinit.pas to C++ to use it in my project. The part where int __fastcall LoadNewResourceModule(LCID locale); is called works fine, in fact I can even call it prior to Application->Initialize() and it will load the proper language at startup. However, the part that calls void __fastcall ReinitializeForms(void); does not work, and gives a runtime error:
Resource TControl not found
Here is the dirty version of .cpp, and .h, I've yet to clean it up and comment it properly, at this point the thing just has to work fully. Please help me sort this out.
//---------------------------------------------------------------------------
#include <System.Classes.hpp>
#include <SysInit.hpp>
#include <Vcl.Forms.hpp>
#pragma hdrstop
#include "reinit.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
class TAsInheritedReader : public TReader
{
public:
void __fastcall ReadPrefix(TFilerFlags &_flags, int &_aChildPos);
inline __fastcall TAsInheritedReader(TStream* Stream, int BufSize) : TReader(Stream, BufSize) {}
};
//---------------------------------------------------------------------------
void __fastcall TAsInheritedReader::ReadPrefix(TFilerFlags &_flags, int &_aChildPos)
{
TReader::ReadPrefix(_flags, _aChildPos);
_flags = _flags << ffInherited;
}
//---------------------------------------------------------------------------
int __fastcall SetResourceHInstance(int _newInstance)
{
PLibModule CurModule = LibModuleList;
while(CurModule != NULL) {
if (reinterpret_cast<void*>(CurModule->Instance) == HInstance) {
if (CurModule->ResInstance != CurModule->Instance) {
FreeLibrary(reinterpret_cast<HMODULE>(CurModule->ResInstance));
CurModule->ResInstance = _newInstance;
return _newInstance;
}
CurModule = CurModule->Next;
}
}
return 0;
}
//---------------------------------------------------------------------------
int __fastcall LoadNewResourceModule(LCID locale)
{
wchar_t FileName[260];
PChar P;
wchar_t LocaleName[4];
int NewInst = 0;
GetModuleFileName(HInstance, FileName, sizeof(FileName));
GetLocaleInfo(locale, LOCALE_SABBREVLANGNAME, LocaleName, sizeof(LocaleName));
P = PChar(&FileName) + lstrlen(FileName);
while((*P != L'.') && (P != reinterpret_cast<PChar>(&FileName))) {
--P;
}
if (P != reinterpret_cast<PChar>(&FileName)) {
++P;
if (LocaleName[0] != L'\0') {
NewInst = reinterpret_cast<int>(LoadLibraryEx(FileName, 0, LOAD_LIBRARY_AS_DATAFILE));
if (NewInst == 0) {
LocaleName[2] = L'\0';
lstrcpy(P, LocaleName);
NewInst = reinterpret_cast<int>(LoadLibraryEx(FileName, 0, LOAD_LIBRARY_AS_DATAFILE));
}
}
}
if (NewInst != 0) {
return SetResourceHInstance(NewInst);
}
return 0;
}
//---------------------------------------------------------------------------
bool __fastcall InternalReloadComponentRes(const String ResName, THandle HInst, TComponent* Instance)
{
//TResourceStream* ResStream = new TResourceStream;
//TAsInheritedReader* AsInheritedReader = new TAsInheritedReader;
if (HInst == 0) {
HInst = reinterpret_cast<THandle>(HInstance);
}
THandle HRsrc = reinterpret_cast<THandle>(FindResource((HMODULE)HInst, (LPCWSTR)ResName.w_str(), (LPCWSTR)RT_RCDATA));
if(HRsrc != 0) {
return false;
}
/* THIS IS THE OFFENDING LINE OF CODE THAT THROWS EXCEPTION
I checked HInst, it is not 0...
ResName = "TControl"
and it throws exception here for some reason
saying resource tcontrol not found
*/
TResourceStream* ResStream = new TResourceStream(HInst, ResName, RT_RCDATA);
try {
TAsInheritedReader* AsInheritedReader = new TAsInheritedReader(ResStream, 4096);
try {
Instance = AsInheritedReader->ReadRootComponent(Instance);
} __finally {
delete AsInheritedReader;
}
}
__finally {
delete ResStream;
}
return true;
}
//---------------------------------------------------------------------------
bool __fastcall InitComponent(TClass ClassType)
{
if ((ClassType->ClassName() == "TComponent") || (ClassType->ClassName() == "RootAncestor")) {
return false;
}
InitComponent(ClassType->ClassParent());
return InternalReloadComponentRes(ClassType->ClassName(), FindResourceHInstance(FindClassHInstance(ClassType)), (TComponent*)&ClassType);
}
//---------------------------------------------------------------------------
bool __fastcall ReloadInheritedComponent(TComponent* Instance)
{
return InitComponent(Instance->ClassType());
}
//---------------------------------------------------------------------------
void __fastcall ReinitializeForms(void)
{
for(int i=0; i<Screen->FormCount-1; i++) {
ReloadInheritedComponent(Screen->Forms[i]);
}
}
#ifndef _reinit_h
#define _reinit_h
#include <windows.h>
extern int __fastcall LoadNewResourceModule(LCID locale);
extern void __fastcall ReinitializeForms(void);
#endif
You don't really need to translate the code at all. You can use Delphi .pas units as-is in C++Builder projects. Simply add the .pas file to your project and compile it, the IDE will generate a .hpp file that you can then #include in your C++ code.
In any case, your translation is not correct in many places.
For instance, the original code wasn't written with Unicode in mind, but you are using Unicode strings in your code. Expressions like sizeof(FileName) and sizeof(LocaleName) are the wrong buffer sizes to pass to the Win32 APIs being used, which can potentially allow buffer overflows. The code was clearly expecting BYTE-sized narrow characters, not WORD-sized wide characters.
It also looks like the original code was not written with 64-bit in mind, either. It is using 32-bit integers in places where 64-bit integers would be needed (for resource handles, etc).
So, the original code needs some updating to support modern systems properly.
But also, your translation of InitComponent() is wrong. It is using strings where the original code is using metaclass references instead, and it is passing the wrong value in the last parameter of InternalReloadComponentRes(), which you have not even declared correctly.
And also, your loop in ReinitializeForms() is skipping the last TForm in the Screen->Forms[] array.
Now, that all being said, try something more like this:
ReInit.h
#ifndef REINIT_H
#define REINIT_H
void __fastcall ReinitializeForms();
NativeUInt __fastcall LoadNewResourceModule(unsigned long Locale);
#endif
ReInit.cpp
#include "ReInit.h"
#include <Windows.hpp>
#include <SysInit.hpp>
#include <SysUtils.hpp>
#include <Classes.hpp>
#include <Forms.hpp>
#include <memory>
class TAsInheritedReader : public TReader
{
public:
void __fastcall ReadPrefix(TFilerFlags &Flags, int &AChildPos) override;
};
void __fastcall TAsInheritedReader::ReadPrefix(TFilerFlags &Flags, int &AChildPos)
{
TReader::ReadPrefix(Flags, AChildPos);
Flags << ffInherited;
}
NativeUInt __fastcall SetResourceHInstance(NativeUInt NewInstance)
{
PLibModule CurModule = LibModuleList;
while (CurModule)
{
if (CurModule->Instance == HInstance)
{
if (CurModule->ResInstance != CurModule->Instance)
::FreeLibrary(reinterpret_cast<HMODULE>(CurModule->ResInstance));
CurModule->ResInstance = NewInstance;
return NewInstance;
}
CurModule = CurModule->Next;
}
return 0;
}
NativeUInt __fastcall LoadNewResourceModule(unsigned long Locale)
{
WCHAR FileName[MAX_PATH+1] = {};
::GetModuleFileNameW(reinterpret_cast<HMODULE>(HInstance), FileName, MAX_PATH+1);
WCHAR LocaleName[5] = {};
::GetLocaleInfoW(Locale, LOCALE_SABBREVLANGNAME, LocaleName, 5);
LPWSTR P = &FileName[lstrlenW(FileName)];
while ((*P != L'.') && (P != FileName)) --P;
HMODULE NewInst = nullptr;
if (P != FileName)
{
++P;
if (LocaleName[0] != L'\0')
{
// Then look for a potential language/country translation
lstrcpyW(P, LocaleName);
NewInst = LoadLibraryEx(FileName, 0, LOAD_LIBRARY_AS_DATAFILE);
if (!NewInst)
{
// Finally look for a language only translation
LocaleName[2] = L'\0';
lstrcpyW(P, LocaleName);
NewInst = LoadLibraryEx(FileName, 0, LOAD_LIBRARY_AS_DATAFILE);
}
}
}
if (NewInst)
return SetResourceHInstance(reinterpret_cast<NativeUInt>(NewInst));
return 0;
}
bool __fastcall InternalReloadComponentRes(const UnicodeString &ResName, NativeUInt HInst, TComponent* &Instance)
{
// avoid possible EResNotFound exception
if (HInst == 0) HInst = HInstance;
HRSRC HRsrc = FindResourceW(reinterpret_cast<HMODULE>(HInst), ResName.c_str(), MAKEINTRESOURCEW(10)/*RT_RCDATA*/);
if (!HRsrc) return false;
auto ResStream = std::make_unique<TResourceStream>(HInst, ResName, MAKEINTRESOURCEW(10)/*RT_RCDATA*/);
auto AsInheritedReader = std::make_unique<TAsInheritedReader>(ResStream.get(), 4096);
Instance = AsInheritedReader->ReadRootComponent(Instance);
return true;
}
bool __fastcall ReloadInheritedComponent(TComponent *Instance, TClass RootAncestor)
{
const auto InitComponent = [&Instance,RootAncestor](TClass ClassType) -> bool
{
auto InitComponent_impl = [&Instance,RootAncestor](TClass ClassType, auto& InitComponent_ref) -> bool
{
if ((ClassType == __classid(TComponent)) || (ClassType == RootAncestor)) return false;
bool Result = InitComponent_ref(ClassType->ClassParent(), InitComponent_ref);
return InternalReloadComponentRes(ClassType->ClassName(), FindResourceHInstance(FindClassHInstance(ClassType)), Instance) || Result;
}
return InitComponent_impl(ClassType, InitComponent_impl);
}
return InitComponent(Instance->ClassType());
}
void __fastcall ReinitializeForms()
{
int Count = Screen->FormCount;
for(int i = 0; i < Count; ++i)
{
ReloadInheritedComponent(Screen->Forms[I], __classid(TForm));
}
}
My environment:
RadStudio 10.2 Tokyo (and also XE4)
I was implementing a copy property method to copy TShape properties.
Following is what I implemented:
//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
// set Shape1 color to [clWhite]
Shape1->Brush->Color = clRed; // clWhite
Shape2->Brush->Color = clAqua;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::copyProperties(TControl *srcCtrl, TControl *dstCtrl)
{
// to Keep original names
String orgName_src = srcCtrl->Name;
String orgName_dst = dstCtrl->Name;
// copy properties
TMemoryStream *strm = new TMemoryStream;
Shape1->Name = L""; // to avoid source collision
try {
strm->WriteComponent(srcCtrl);
strm->Position = 0;
strm->ReadComponent(dstCtrl);
}
__finally
{
delete strm;
}
srcCtrl->Name = orgName_src;
dstCtrl->Name = orgName_dst;
}
void __fastcall TForm1::Button1Click(TObject *Sender)
{
copyProperties((TControl *)Shape1, (TControl *)Shape2);
// shift to avoid position-overlapping
Shape2->Left = Shape1->Left + 150;
}
//---------------------------------------------------------------------------
The code seems work fine.
But there is a single case, in which the code does not work.
i.e. when the Brush->Color = clWhite for Shape1.
This bug? can be reproduced also for XE4.
I wonder why only the clWhite has this kind of bug? Other colors does not have this kind of bug.
There is no bug in the streaming. It is operating as designed. You are simply using it in a way that it is not intended for.
clWhite is the declared default value of the TBrush.Color property. The DFM streaming system does not stream properties that are currently set to their default values, unless those properties are declared as nodefault or stored=true. TBrush.Color is neither. So the current Brush.Color value will not be streamed when it is set to clWhite.
Consider using the RTTI system directly instead of using the DFM system to copy properties from one object to another. Then you can copy property values regardless of defaults, if you choose to do so. And you can opt to ignore the Name property without having to (re)store it each time.
For example:
#include <System.TypInfo.hpp>
void __fastcall TForm1::copyProperties(TControl *srcCtrl, TControl *dstCtrl)
{
PTypeInfo pDstTypeInfo = static_cast<PTypeInfo>(dstCtrl->ClassInfo());
PPropList srcPropList;
int srcPropCount = GetPropList(srcCtrl, srcPropList);
try
{
for (int i = 0; i < srcPropCount; ++i)
{
PPropInfo pSrcPropInfo = (*srcPropList)[i];
if (pSrcPropInfo->Name == "Name") continue;
PTypeInfo pSrcPropTypeInfo = *(pSrcPropInfo->PropType);
if (pSrcPropTypeInfo->Kind == tkClass)
{
PPropInfo pDstPropInfo = GetPropInfo(pDstTypeInfo, pSrcPropInfo->Name, TTypeKinds() << tkClass);
if (pDstPropInfo)
{
TPersistent *pDstObj = static_cast<TPersistent*>(GetObjectProp(dstCtrl, pDstPropInfo, __classid(TPersistent)));
if (pDstObj)
{
TPersistent *pSrcObj = static_cast<TPersistent*>(GetObjectProp(srcCtrl, pSrcPropInfo, __classid(TPersistent)));
pDstObj->Assign(pSrcObj);
}
}
}
else
{
PPropInfo pDstPropInfo = GetPropInfo(pDstTypeInfo, pSrcPropInfo->Name);
if (pDstPropInfo)
{
Variant value = GetPropValue(srcCtrl, pSrcPropInfo);
SetPropValue(dstCtrl, pDstPropInfo, value);
}
}
}
}
__finally
{
FreeMem(srcPropList);
}
}
Alternatively:
#include <System.Rtti.hpp>
void __fastcall TForm1::copyProperties(TControl *srcCtrl, TControl *dstCtrl)
{
TRttiContext ctx;
TRttiType *pSrcType = ctx.GetType(srcCtrl->ClassInfo());
TRttiType *pDstType = ctx.GetType(dstCtrl->ClassInfo());
DynamicArray<TRttiProperty*> srcProps = pSrcType->GetProperties();
for (int i = 0; i < srcProps.Length; ++i)
{
TRttiProperty *pSrcProp = srcProps[i];
if (pSrcProp->Name == L"Name") continue;
if (pSrcProp->PropertyType->TypeKind == tkClass)
{
TRttiProperty *pDstProp = pDstType->GetProperty(pSrcPropInfo->Name);
if ((pDstProp) && (pDstProp->PropertyType->TypeKind == tkClass))
{
TPersistent *pDstObj = dynamic_cast<TPersistent*>(pDstProp->GetValue(dstCtrl).AsObject());
if (pDstObj)
{
TPersistent *pSrcObj = dynamic_cast<TPersistent*>(pSrcProp->GetValue(srcCtrl).AsObject());
pDstObj->Assign(pSrcObj);
}
}
}
else
{
TRttiProperty *pDstProp = pDstType->GetProperty(pSrcPropInfo->Name);
if (pDstProp)
{
TValue value = pSrcProp->GetValue(srcCtrl);
pDstProp->SetValue(dstCtrl, value);
}
}
}
}
My Environment: C++ Builder XE4
how to copy all the TLabels parented with a TPanel on delphi to another TPanel?
I would like to implement above code in C++ Builder.
I do not know how to implement below in C++ Builder.
if ParentControl.Controls[i] is TLabel then
Are there any functions to get type as TLabel or some other?
You can use ClassType method as:
if(Controls[i]->ClassType() == __classid(TLabel))
{
...
}
Use dynamic_cast:
if (dynamic_cast<TLabel*>(ParentControl->Controls[i]) != NULL)
Here is a translation of that code:
void __fastcall CopyLabels(TWinControl *ParentControl, TWinControl *DestControl)
{
for(int i = 0; i < ParentControl->ControlCount; ++i)
{
if (dynamic_cast<TLabel*>(ParentControl->Controls[i]) != NULL)
{
TLabel *ALabel = new TLabel(DestControl);
ALabel->Parent = DestControl;
ALabel->Left = ParentControl->Controls[i]->Left;
ALabel->Top = ParentControl->Controls[i]->Top;
ALabel->Width = ParentControl->Controls[i]->Width;
ALabel->Height = ParentControl->Controls[i]->Height;
ALabel->Caption= static_cast<TLabel*>(ParentControl->Controls[i])->Caption;
//you can add manually more properties here like font or another
}
}
}
With that said, this would be slightly more efficient:
void __fastcall CopyLabels(TWinControl *ParentControl, TWinControl *DestControl)
{
int count = ParentControl->ControlCount;
for(int i = 0; i < count; ++i)
{
TLabel *SourceLabel = dynamic_cast<TLabel*>(ParentControl->Controls[i]);
if (SourceLabel != NULL)
{
TLabel *ALabel = new TLabel(DestControl);
ALabel->Parent = DestControl;
ALabel->SetBounds(SourceLabel->Left, SourceLabel->Top, SourceLabel->Width, SourceLabel->Height);
ALabel->Caption = SourceLabel->Caption;
//you can add manually more properties here like font or another
}
}
}
I found ClassName() method.
Following seems working.
static bool isTCheckBox(TControl *srcPtr)
{
if (srcPtr->ClassName() == L"TCheckBox") {
return true;
}
return false;
}
I am new in programming. Actually I am in 2nd year of college and starting an internship. They want me to do a program in C++ builder but I only know C. What I studied. And I don't have any knowledge about OOP.
So my question is.
I have TEdit1 and I want to verify if the data introduced in that textbox is a number. I know to verify if it is a number but I don't know how to put data from TEdit into string.
I wrote some code but it doesn't work.
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int Size = Edit1->GetTextLen(); //Get length of string in Edit1
Size++; //Add room for null character
Char *Buffer = new Char[Size]; //Creates Buffer dynamic variable
std::auto_ptr<Char> Buffer(new Char[Size]);
Edit1->GetTextBuf(Buffer.get(),Size); //Puts Edit1->Text into Buffer
ShowMessage(Buffer);
}
And I get these errors:
E2034 Cannot convert 'std::auto_ptr<wchar_t>' to 'UnicodeString'
E2342 Type mismatch in parameter 'Msg' (wanted 'const UnicodeString', got std::auto_ptr<wchar_t>')
Can you please explain what i did wrong, or where i can found Embarcadero C++ Builder tutorials? I searched all google and didn't find something to help me.
Your code has several mistakes in it:
you are declaring two Buffer variables in the same scope. That is not allowed. You need to remove one of them.
you are passing the std::auto_ptr itself to ShowMessage(), but it expects a System::UnicodeString instead, thus the compiler error message. You can use the std::auto_ptr::get() method to get the wchar_t* pointer and pass it to ShowMessage(), as UnicodeString has a constructor that accepts wchar_t* as input:
ShowMessage(Buffer.get());
despite the above, you actually cannot use a pointer from new[] with std::auto_ptr to begin with. std::auto_ptr uses delete instead of delete[] to free the memory being pointed at. You must always use delete with new, and delete[] with new[]. So, while the code will compile, it will not free the memory correctly at runtime. C++11 introduced a new std::unique_ptr class to replace std::auto_ptr, and std::unique_ptr supports new[] and delete[] (however, C++Builder's 32bit compiler does not support C++11 yet - that is in the works - but its 64bit compiler does):
#include <memory>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int Size = Edit1->GetTextLen(); //Get length of string in Edit1
Size++; //Add room for null character
std::unique_ptr<Char[]> Buffer(new Char[Size]); //Creates Buffer dynamic variable
Edit1->GetTextBuf(Buffer.get(), Size); //Puts Edit1->Text into Buffer
ShowMessage(Buffer.get());
}
Now, with that said, if you are going to continue using C++Builder, you should learn how to use its built-in functionalities, like UnicodeString, which the RTL/VCL relies heavily on (use the System::String alias for most code, use UnicodeString directly only when absolutely necessary).
Your example can be vastly simplified using the TEdit::Text property:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
String s = Edit1->Text; //Get string in Edit1
ShowMessage(s);
}
The simplest solution to your problem would be to use the TCSpinEdit component instead of TEdit, as TCSpinEdit only allows numeric input in the first place, and has a Value property that returns an int:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number = CSpinEdit1->Value;
ShowMessage("It is a number");
// use number as needed...
}
But, if you have to stick with TEdit, there are many ways to check a UnicodeString for numeric content.
You can set the TEdit::NumbersOnly property to true so the user cannot enter a non-numeric value (unless they use copy/paste, but let's ignore that for the moment), and then use the RTL's StrToInt() function, or System::UnicodeString::ToInt() method, to convert it as-is:
#include <System.SysUtils.hpp>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number;
try
{
number = StrToInt(Edit1->Text);
// or: number = Edit1->Text.ToInt();
}
catch (const EConvertError&)
{
// not a number, do something else...
ShowMessage("It is not a number");
return;
}
ShowMessage("It is a number");
// use number as needed...
}
Or you can use the RTL's System::Sysutils::TryStrToInt() function:
#include <System.SysUtils.hpp>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number;
if (TryStrToInt(Edit1->Text, number))
{
// use number as needed...
ShowMessage("It is a number");
}
else
{
// not a number, do something else...
ShowMessage("It is not a number");
}
}
Or you can use the STL's std::wistringstream class:
#include <sstream>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number;
std::wistringstream iss(Edit1->Text.c_str());
if (iss >> number)
{
// use number as needed...
ShowMessage("It is a number");
}
else
{
// not a number, do something else...
ShowMessage("It is not a number");
}
}
Or, since you have a C background, you can use the C _wtoi() function (which doesn't offer much in the way of error checking):
#include <cstdlib>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number = std::_wtoi(Edit1->Text.c_str());
if (number != 0)
{
// use number as needed...
ShowMessage("It is a valid number");
}
else
{
// not a number, do something else...
ShowMessage("It is not a valid number");
}
}
Or you can use the C wcstol() function:
#include <cstdlib>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
String s = Edit1->Text;
Char *p = s.c_str(), *end;
int number = std::wcstol(p, &end, 10);
if (end != p)
{
// use number as needed...
ShowMessage("It is a number");
}
else
{
// not a number, do something else...
ShowMessage("It is not a number");
}
}
Or you can use the C swscanf() function:
#include <cstdio>
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int number;
if (std::swscanf(Edit1->Text.c_str(), L"%d", &number) == 1)
{
// use number as needed...
ShowMessage("It is a number");
}
else
{
// not a number, do something else...
ShowMessage("It is not a number");
}
}
How do I check through all the components of a form and verify that components are of type TEdit?
You can use the dynamic_cast operator.
Excuse me if I'm wrong, but won't embarcadero automatically add all form-component object pointers to the class definition ( in the header file )..
Such as:
class TFormSomeForm : public TForm
{
__published:
TEdit *SomeEditBox;
TEdit *AnotherEditBox;
...
}
Meaning that you can tell from the header which components are of type TEdit.
Or you can click on the components in the Design View and the Object Inspector will show the type.
My function sets Text property of all edits in a TWinControl and its children.
void __fastcall SetEditsText(TWinControl* winControl, UnicodeString editsText)
{
for (int c = 0; c < winControl->ControlCount; c++)
{
TControl* ctrl = winControl->Controls[c];
TWinControl* wc = dynamic_cast<TWinControl*>(ctrl);
// Check if it's grouping component
if (wc != NULL)
{
// Set edits of children
SetEditsText(wc, editsText);
}
else
{
if (ctrl->ClassType() == __classid(TEdit))
{
TEdit* ecomp = (TEdit*) ctrl;
ecomp->Text = editsText;
}
}
}
}
Using:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
SetEditsText(form1, ""); // Clear all edits
}