Project myProject = m_oProject; // A valid project
Page myPage = myProject.Pages[0]; // A valid Page object

// Use a filter to get only functions with category 'Motor'
myPage.Filter.FunctionCategory = Eplan.EplApi.Base.Enums.FunctionCategory.Motor;

// Place all functions with category 'Motor' on page myPage
Function[] functions = myPage.Functions;

// Another way to do the same:
// Use a filter to get only functions with category 'Motor'
FunctionsFilter myFunctionsFilter = new FunctionsFilter();
myFunctionsFilter.FunctionCategory = Eplan.EplApi.Base.Enums.FunctionCategory.Motor;
myFunctionsFilter.Page = myPage;
DMObjectsFinder objFinder = new DMObjectsFinder(myProject);

// Place all functions with category 'Motor' on page myPage
functions = objFinder.GetFunctions(myFunctionsFilter);

Project myProject = m_oProject; // A valid project
Page myPage = myProject.Pages[0]; // A valid Page object

// Define test property
MultiLangString mlsTestValue = new MultiLangString();
mlsTestValue.AddString(ISOCode.Language.L_de_DE, "Test043c");
string strPropertyIdentyfingName = "Page.Test043c";
UserDefinedPropertyDefinition oUDPD = UserDefinedPropertyDefinition.Create(myProject, strPropertyIdentyfingName, UserDefinedPropertyDefinition.Enums.ClientType.Page);

// Set test property on myPage
myPage.Properties[strPropertyIdentyfingName] = mlsTestValue;

// Search page with property value
DMObjectsFinder objFinder = new DMObjectsFinder(myProject);
PagesFilter pagesFilter = new PagesFilter();
PagePropertyList pagePropertyList = new PagePropertyList();
AnyPropertyId anyPropertyId = new AnyPropertyId(myProject, strPropertyIdentyfingName);

pagePropertyList[anyPropertyId] = mlsTestValue;
pagesFilter.SetFilteredPropertyList(pagePropertyList);
Page[] arrPages1 = objFinder.GetPages(pagesFilter);