LiquidXML DataBinding导出XML时如何抑制xs:type属性

I’ve run into this exact scenario before with LiquidXML’s DataBinder—those auto-added xs:type attributes can be frustrating when your target XML schema doesn’t require them. Here’s how to fix it, depending on where you are in the workflow:

1. Adjust DataBinder Settings Before Generating Code #

If you haven’t already generated your VB.NET classes (or can regenerate them), this is the cleanest approach:

• Open your LiquidXML DataBinder project.
• Navigate to the Serialization Settings (look under project properties or code generation options—labeling may vary slightly).
• Look for an option like "Suppress xsi:type Attributes" or "Omit Type Hints for Derived Classes" and enable it.
• Regenerate your VB.NET classes. The auto-generated ToXML methods will now omit the xs:type attributes for derived types that the schema explicitly expects.

2. Modify Generated Code Manually #

If regenerating code isn’t an option, tweak the generated classes to remove the type hint:

• Locate the class property that’s producing the xs:type attribute (e.g., the patient property in your pair class).
• If the property is declared as a base type (like Public Property patient As Person where Patient inherits from Person), update the property’s XML attribute to explicitly specify the derived type:

  <XmlElement(Type:=GetType(Patient))>
  Public Property patient As Patient
  

  This tells the serializer that the property will always be a Patient instance, so it doesn’t need to add the xs:type hint.
• Alternatively, check if your base class has an XmlInclude attribute for Patient—if you don’t need polymorphism elsewhere, removing this will make the serializer skip the type attribute.

3. Replace the Auto-Generated ToXML Method with Custom Serialization #

If the above methods don’t work, roll your own serialization logic to override the auto-generated code:

• Create a custom method in your class instead of using the auto-generated ToXML:

  Public Function ToXmlWithoutTypeHints() As String
      Dim serializer As New XmlSerializer(GetType(Pair))
      Dim namespaces As New XmlSerializerNamespaces()
      ' Remove default namespaces if your schema doesn't require them
      namespaces.Add("", "")
      
      Using writer As New StringWriter()
          serializer.Serialize(writer, Me, namespaces)
          Return writer.ToString()
      End Using
  End Function
  

• The key here is serializing the concrete type directly (or ensuring the property is typed as Patient instead of a base class)—this removes the need for the serializer to add a xs:type attribute to disambiguate the type.

Quick Context #

The xs:type attribute is added by default when dealing with polymorphic types (e.g., Patient inheriting from a base class) to let XML parsers know the actual element type. LiquidXML adds this automatically if your XSD defines inheritance. If your target system doesn’t need this hint (or your schema expects the concrete type directly), the steps above will suppress it.

内容的提问来源于stack exchange，提问作者Zero-G.