About Schema Wrapper Libraries (C#)
The default mapping of XML Schema types to C# data types is as follows.
XML Schema | C# | Remarks |
|---|---|---|
xs:string | string | |
xs:boolean | bool | |
xs:decimal | decimal | xs:decimal has unlimited range and precision, mapped to decimal for efficiency reasons. |
xs:float, xs:double | double | |
xs:long | long | |
xs:unsignedLong | ulong | |
xs:int | int | |
xs:unsignedInt | uint | |
xs:dateTime, date, time, gYearMonth, gYear, gMonthDay, gDay, gMonth | ||
xs:duration | ||
xs:hexBinary and xs:base64Binary | byte[] | Encoding and decoding of binary data is done automatically. |
xs:anySimpleType | string |
All XML Schema types not contained in this list are derived types, and mapped to the same C# type as their respective base type.
Generated Classes
For each type in the schema, a class is generated that contains a member for each attribute and element of the type. The members are named the same as the attributes or elements in the original schema (in case of possible collisions, a number is appended). For simple types, assignment and conversion operators are generated. For simple types with enumeration facets, the methods GetEnumerationValue() and SetEnumerationValue(int) can be used together with generated constants for each enumeration value. In addition, the method StaticInfo() allows accessing schema information as one of the following types:
Classes generated from complex types include the method SetXsiType(), which enables you to set the xsi:type attribute of the type. This method is useful when you want to create XML instance elements of a derived type.
In addition to the classes for the types declared in the XML Schema, a document class (identified with "Doc" below) is generated. It contains all possible root elements as members, and various other methods. For more information about the class, see [YourSchema].[Doc].
Note: The actual class name depends on the name of the .xsd schema.
For each member attribute or element of a schema type, a new class is generated. For more information about such classes, see:
[YourSchemaType].MemberAttribute
[YourSchemaType].MemberElement
Note: The actual class names depend on the name of the schema attribute or element.
Error Handling
Errors are reported by exceptions. The following exception classes are defined in the namespace Altova:
Class | Base Class | Description |
|---|---|---|
ConversionException | Exception | Exception thrown when a type conversion fails |
StringParseException | ConversionException | A value in the lexical space cannot be converted to value space. |
DataSourceUnavailableException | System.Exception | A problem occurred while loading an XML instance. |
DataTargetUnavailableException | System.Exception | A problem occurred while saving an XML instance. |
In addition, the following .NET exceptions are commonly used:
Class | Description |
|---|---|
System.Exception | Base class for runtime errors |
System.ArgumentException | A method was called with invalid argument values, or a type conversion failed. |
System.FormatException | A value in the lexical space cannot be converted to value space. |
System.InvalidCastException | A value cannot be converted to another type. |
System.OverflowException | A source value cannot be represented in target domain. |
Accessing schema information
The generated library allows accessing static schema information via the following classes:
The properties that return one of the metadata classes return null if the respective property does not exist.