As I don’t use regular expressions that often I always forget the syntax. So I thought I just put a basic replace pattern up here.
This method takes a schema, finds all places where is says schemaLocation=”whatever” in a text and changes this to schemaLocation=”whatever.xsd“ and then returns the schema.

private XmlSchema FixSchemaLocation(XmlSchema schema)
{
System.Text.RegularExpressions.Regex locationReplacePattern […]