C++ Builder中从.res文件加载字符串与rc_data的示例求助

Awesome that your bitmap resource loading is working flawlessly already! Let's walk through solid, practical examples for loading string and RC_DATA resources in C++ Builder—these should fit right in with your existing setup.

Loading String Resources #

First, double-check your .rc file includes a STRINGTABLE entry (this is what gets compiled into your .res file). Here's a sample definition:

STRINGTABLE
BEGIN
    100, "Welcome to C++ Builder Resource Strings"
    101, "This is a test string pulled from resources"
END

Option 1: Win32 API LoadString() (Direct & Flexible) #

This is the standard Win32 approach, great for full control:

void LoadAndDisplayResourceString()
{
    wchar_t strBuffer[256]; // Adjust buffer size based on your longest string
    // Load the string with resource ID 100
    int stringLength = LoadStringW((HINSTANCE)HInstance, 100, strBuffer, sizeof(strBuffer)/sizeof(wchar_t));
    
    if (stringLength > 0)
    {
        // Use the string however you need—display in a message, assign to a control, etc.
        ShowMessage(strBuffer);
        Edit1->Text = String(strBuffer);
    }
    else
    {
        ShowMessage("Oops: Failed to load the string resource!");
    }
}

Option 2: C++ Builder TResourceString (VCL-Native Simplicity) #

If you prefer a more VCL-friendly method, declare a resource string directly and use it like any other String:

// Declare this in your header or implementation file
TResourceString ResStr101 = {101};

void UseVCLResourceString()
{
    String myLoadedString = ResStr101;
    Label1->Caption = "Loaded Resource String: " + myLoadedString;
    Memo1->Lines->Add(myLoadedString);
}

Loading RC_DATA Resources #

RC_DATA is ideal for embedding binary data (custom files, config blobs, raw bytes, etc.). First, define it in your .rc file—here are two common ways:

// Option 1: Embed an external file (e.g., a binary config or text file)
MY_CUSTOM_BLOB RCDATA "my_external_file.bin"

// Option 2: Embed raw binary data directly in the .rc file
MY_RAW_BYTES RCDATA {
    0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, // ASCII "Hello "
    0x57, 0x6F, 0x72, 0x6C, 0x64        // ASCII "World"
}

Extracting RC_DATA in Code #

Use the Win32 resource API to access the embedded data:

void LoadAndProcessRCData()
{
    // Step 1: Locate the resource
    HRSRC resourceHandle = FindResourceW((HINSTANCE)HInstance, L"MY_CUSTOM_BLOB", RT_RCDATA);
    if (!resourceHandle)
    {
        ShowMessage("Failed to locate RC_DATA resource!");
        return;
    }

    // Step 2: Load the resource into memory
    HGLOBAL resourceMemory = LoadResource((HINSTANCE)HInstance, resourceHandle);
    if (!resourceMemory)
    {
        ShowMessage("Failed to load RC_DATA into memory!");
        return;
    }

    // Step 3: Lock to get a pointer to the raw data
    const void* dataPointer = LockResource(resourceMemory);
    DWORD dataSize = SizeofResource((HINSTANCE)HInstance, resourceHandle);

    if (dataPointer && dataSize > 0)
    {
        // Example 1: Save the data to an external file
        TFileStream* outputStream = new TFileStream("extracted_data.bin", fmCreate);
        outputStream->Write(dataPointer, dataSize);
        delete outputStream;
        ShowMessage("RC_DATA extracted to file successfully!");

        // Example 2: Process as text (if the embedded data is a UTF-16 string)
        String textContent = String((wchar_t*)dataPointer, dataSize / sizeof(wchar_t));
        Memo1->Lines->Add("Extracted Text: " + textContent);
    }

    // Note: No need to manually free the resource—Windows manages it automatically
}

Quick Tips #

• Match Resource Names/IDs Exactly: Resource names are case-sensitive when using string identifiers (like MY_CUSTOM_BLOB), so double-check your code and .rc file match.
• Unicode Awareness: Use the wide-character API functions (the W suffix, like LoadStringW) to avoid encoding issues with Unicode strings.
• Error Handling: Always check the return values of resource functions—they'll help you debug if a resource isn't loading as expected.

内容的提问来源于stack exchange，提问作者Augusto Imperatore