前言

遇到个需求，就是在qt客户端显示服务器上的pdf文档，文档以base64格式返回给客户端。以下是实现方法：

1、在pro文件增加以下代码：

INCLUDEPATH += $$PWD/PDFiumSDK/include/publicDEPENDPATH += $$PWD/PDFiumSDK/include/publicLIBS += -l$$PWD/PDFiumSDK/lib/x86/pdfium

2、pdf转图片
 

FPDF_InitLibrary();
// base64的数据要先转为二进制
QByteArray bytes = QByteArray::fromBase64(strBase64Code.toUtf8());
FPDF_DOCUMENT doc = FPDF_LoadMemDocument(bytes.data(), bytes.size(), "");
int pageCount = FPDF_GetPageCount(doc);
for (int t = 0; t < pageCount; t++)
{FPDF_PAGE page = FPDF_LoadPage(doc, t);int width = static_cast<int>(FPDF_GetPageWidth(page));int height = static_cast<int>(FPDF_GetPageHeight(page));FPDF_BITMAP bitmap = FPDFBitmap_Create(width, height, 0);FPDFBitmap_FillRect(bitmap, 0, 0, width, height, 0xFFFFFFFF);FPDF_RenderPageBitmap(bitmap, page, 0, 0, width, height, 0, 0);const char* buffer = reinterpret_cast<const char* >(FPDFBitmap_GetBuffer(bitmap));// 数据转图片，使用不同的Format可能会有图片失真的现象，要多试几次QImage image((uchar*)buffer, width, height, QImage::Format_RGB32);QLabel *label = new QLabel(this);label->setPixmap(QPixmap::fromImage(image));label->setFixedSize(width, height);// TODO addwidget(label);把label添加到显示控件中FPDF_ClosePage(page);count++;
}
FPDF_CloseDocument(doc);
FPDF_DestroyLibrary();