本文整理汇总了C++中exiv2::exifdata::iterator::getValue方法的典型用法代码示例。如果您正苦于以下问题：C++ iterator::getValue方法的具体用法？C++ iterator::getValue怎么用？C++ iterator::getValue使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类exiv2::exifdata::iterator的用法示例。
在下文中一共展示了iterator::getValue方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: main
// *****************************************************************************
// Main
int main()
try {
// Container for all metadata
Exiv2::ExifData exifData;
// *************************************************************************
// Add to the Exif data
// Create a ASCII string value (note the use of create)
Exiv2::Value* v = Exiv2::Value::create(Exiv2::asciiString);
// Set the value to a string
v->read("1999:12:31 23:59:59");
// Add the value together with its key to the Exif data container
Exiv2::ExifKey key("Exif.Photo.DateTimeOriginal");
exifData.add(key, v);
std::cout << "Added key \"" << key << "\", value \"" << *v << "\"\n";
// Delete the memory allocated by Value::create
delete v;
// Now create a more interesting value (without using the create method)
Exiv2::URationalValue* rv = new Exiv2::URationalValue;
// Set two rational components from a string
rv->read("1/2 1/3");
// Add more elements through the extended interface of rational value
rv->value_.push_back(std::make_pair(2,3));
rv->value_.push_back(std::make_pair(3,4));
// Add the key and value pair to the Exif data
key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
exifData.add(key, rv);
std::cout << "Added key \"" << key << "\", value \"" << *rv << "\"\n";
// Delete memory allocated on the heap
delete rv;
// *************************************************************************
// Modify Exif data
// Find the timestamp metadatum by its key
key = Exiv2::ExifKey("Exif.Photo.DateTimeOriginal");
Exiv2::ExifData::iterator pos = exifData.findKey(key);
if (pos == exifData.end()) throw Exiv2::Error("Key not found");
// Modify the value
std::string date = pos->toString();
date.replace(0,4,"2000");
pos->setValue(date);
std::cout << "Modified key \"" << key
<< "\", new value \"" << pos->value() << "\"\n";
// Find the other key
key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
pos = exifData.findKey(key);
if (pos == exifData.end()) throw Exiv2::Error("Key not found");
// Get a pointer to a copy of the value
v = pos->getValue();
// Downcast the Value pointer to its actual type
rv = dynamic_cast<Exiv2::URationalValue*>(v);
if (rv == 0) throw Exiv2::Error("Downcast failed");
// Modify the value directly through the interface of URationalValue
rv->value_[2] = std::make_pair(88,77);
// Copy the modified value back to the metadatum
pos->setValue(rv);
// Delete the memory allocated by getValue
delete v;
std::cout << "Modified key \"" << key
<< "\", new value \"" << pos->value() << "\"\n";
// *************************************************************************
// Delete metadata from the Exif data container
// Delete the metadatum at iterator position pos
key = Exiv2::ExifKey("Exif.Image.PrimaryChromaticities");
pos = exifData.findKey(key);
if (pos == exifData.end()) throw Exiv2::Error("Key not found");
exifData.erase(pos);
std::cout << "Deleted key \"" << key << "\"\n";
// *************************************************************************
// Finally, write the remaining Exif data to an image file
int rc = exifData.write("img_2158.jpg");
if (rc) {
std::string error = Exiv2::ExifData::strError(rc, "img_2158.jpg");
throw Exiv2::Error(error);
}
return 0;
}
catch (Exiv2::Error& e) {
std::cout << "Caught Exiv2 exception '" << e << "'\n";
return -1;
}