Examples of using FunctionBuilder

For a more detailed understanding of the transition from SQLWhereLanguageDef on FunctionBuilder this article provides basic examples of the refactor that has been implemented on several application projects.

funcSQL

No special changes.

Limit function using langdef

    Function lf = LangDef.GetFunction(LangDef.funcSQL, "sql");

Limit function using FunctionBuilder

	Function lf = FunctionBuilder.BuildSQL("sql");

funcNOT

No special changes.

Limit function using langdef

	Function FuncTrue = LangDef.GetFunction(LangDef.funcEQ, 1, 1);
    Function lf = LangDef.GetFunction(LangDef.funcNOT, FuncTrue);

Limit function using FunctionBuilder

	Function FuncTrue = FunctionBuilder.BuildTrue();
	Function lf = FunctionBuilder.BuildNot(FuncTrue);

funcEQ

The restriction on primary keys is accompanied by a reference to the __Primary Key property, which does not reduce the complexity and readability of the code.

Limit function using langdef

	VariableDef PrimaryKeyVarDef = new VariableDef(LangDef.GuidType, SQLWhereLanguageDef.StormMainObjectKey);
    Function lf = LangDef.GetFunction(
        LangDef.funcEQ,
        PrimaryKeyVarDef,
        TestDataObject1.__PrimaryKey);

Limit function using FunctionBuilder

	Function lf = FunctionBuilder.BuildEquals(TestDataObject1);

funcIN - own primary key

The main disadvantage of funcIN is the need to pass an untyped array with the second argument, the first element of which must be the property path. In the Function Builder the deficiency rather gracefully overcome to construct the function of columns in primary keys do not have to specify SQLWhereLanguageDef.StormMainObjectKey, i.e. it is not necessary to specify the property path (in this case).

Limit function using langdef

    var clientKeys = new List<object> { new VariableDef(langdef.GuidType, SQLWhereLanguageDef.StormMainObjectKey) };
	clientKeys.AddRange(ordKeys);
	Function lf = langdef.GetFunction(langdef.funcIN, clientKeys.ToArray());

Limit function using FunctionBuilder

	Function lf = FunctionBuilder.BuildIn(ordKeys);

funcIN - class field

It is not necessary to use EnumCaption.GetCaptionFor to limit objects to an array of enumerations.

Limit function using langdef

	Function lf = langdef.GetFunction(langdef.funcIN, new VariableDef(langdef.StringType, "СпособВвода"),
		EnumCaption.GetCaptionFor(СпВвода),
		EnumCaption.GetCaptionFor(tСпособВвода.ИмпортАСПенсия));

Limit function using FunctionBuilder

	Function lf = FunctionBuilder.BuildIn<Происхождение>(x => x.СпособВвода, СпВвода, tСпособВвода.ИмпортАСПенсия);

funcExists

The syntax is quite simplified, the BuildExists wrapper method has two overloads:

• Function BuildExists(DetailVariableDef dvd, Function function = null)
• Function BuildExists(string connectMasterPorp, View view, Function function = null)

The main difference is the optional argument function for which the sample will be carried out.

Limit function using langdef

	Function FuncTrue = LangDef.GetFunction(LangDef.funcEQ, 1, 1);
	string ConnectMasterProp = Information.ExtractPropertyName<TestDataObjectDetail>(x => x.TestDataObject);
	DetailVariableDef DetVarDef = FunctionHelper.GetDetailVarDef(TestDataObjectDetail.Views.D, ConnectMasterProp);
	Function lf = LangDef.GetFunction(LangDef.funcExist, DetVarDef, FuncTrue);

Limit function using FunctionBuilder

Overload 1:

	string ConnectMasterProp = Information.ExtractPropertyName<TestDataObjectDetail>(x => x.TestDataObject);
	DetailVariableDef DetVarDef = FunctionHelper.GetDetailVarDef(TestDataObjectDetail.Views.D, ConnectMasterProp);
	Function lf = FunctionBuilder.BuildExists(DetVarDef);

Overload 2:

	string ConnectMasterProp = Information.ExtractPropertyName<TestDataObjectDetail>(x => x.TestDataObject);
	Function lf = FunctionBuilder.BuildExists(ConnectMasterProp, TestDataObjectDetail.Views.D, DetVarDef);

Missing functionality

A more attentive reader can replace that in Function Builder there are no such functions asDatePart, YearPart, Count, SUM, MAX, etc. These functions were not ‘wrapped’ intentionally, because FunctionBuilder is focused on building logical functions, each of which as a result returns a Boolean value. However, many FunctionBuilder methods have overloads that allow you to pass Function as argument.

Summary

Moving from LangDef.GetFunction to FunctionBuilder carries not only quantitative changes in the form of reducing the length of the code, but also qualitative:

• significant increase in code readability for both simple and highly complex functions
• minimize errors when specifying property paths by using lambdas
• simplification of work with primary keys through the use of PKHelper