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XML document questionclass Stuff { Dictionary<string, object> properties; List<Stuff> children; } I'm writing a home made XML 'serialization'. I quote that, because it's not serialization, I'm writing the XML writer myself (without System.Reflection). I'm using a shema like that: <stuff count=2 key1="value1" key2="value2" key3="value3"> <stuf> ......... </stuff> <stuf> ......... </stuff> </stuff> where count = children.Count and key1,2,3 are the keys in the properties dictionary and value1,2,3 their values. properties is to be filled by the user with whatever (s)he wants. Now my problem is: ============== As the user could put whatever (s)he wants in the properties dictionary (s)he could as well create a key named 'count', therefore the 'count' atribute will be present twice in the tag. It's not a problem for my reader (which expect a first count followed by any kind of attribute) but it might be for other people wanting to consume my XML documents. What do you think? it's actually much easier this way... (particularly because this sample output is far from the whole story) Lloyd,
I don't know if its a direct match, but I'll refer you to some work I did with xml serialization and some issues with IDictionary http://sholliday.spaces.live.com/?_c11_BlogPart_n=1&_c11_BlogPart_handle=cns!A68482B9628A842A!125&_c11_BlogPart_FullView=1&_c=BlogPart 9/21/2005 entry (if you have issues, then go to http://sholliday.spaces.live.com/ .....go to the bottom and "see more entries". and find the 9/21/2005 entry titled "XmlSerialization with IDictionary and CollectionBase Objects" ... Show quote "Lloyd Dupont" <net.galador@ld> wrote in message news:O2oajy6vGHA.3364@TK2MSFTNGP02.phx.gbl... > I have a class which looks like that: > > class Stuff > { > Dictionary<string, object> properties; > List<Stuff> children; > } > > I'm writing a home made XML 'serialization'. > I quote that, because it's not serialization, I'm writing the XML writer > myself (without System.Reflection). > > > I'm using a shema like that: > <stuff count=2 key1="value1" key2="value2" key3="value3"> > <stuf> > ......... > </stuff> > <stuf> > ......... > </stuff> > </stuff> > > where count = children.Count > and key1,2,3 are the keys in the properties dictionary and value1,2,3 their > values. > > properties is to be filled by the user with whatever (s)he wants. > > > Now my problem is: > ============== > > As the user could put whatever (s)he wants in the properties dictionary > (s)he could as well create a key named 'count', therefore the 'count' > atribute will be present twice in the tag. > > It's not a problem for my reader (which expect a first count followed by any > kind of attribute) but it might be for other people wanting to consume my > XML documents. > > What do you think? > > it's actually much easier this way... > (particularly because this sample output is far from the whole story) > > Lloyd Dupont wrote:
> As the user could put whatever (s)he wants in the properties dictionary Any XML parser/XML API can find the count of stuff elements by > (s)he could as well create a key named 'count', therefore the 'count' > atribute will be present twice in the tag. > > It's not a problem for my reader (which expect a first count followed by any > kind of attribute) but it might be for other people wanting to consume my > XML documents. parsing/counting the child stuff elements so I am not sure it is necessary to have an attribute giving that count value. As for trying to have two attributes of the name 'count', that is not allowed in XML and breaks well-formedness rules. Also attributes of XML elements are not ordered. I am also not sure how with Dictionary<string, object> any object you can have in there fits in an XML attribute value. 1. the count attribute has a performance 'raison d'etre'
there are few instance where it could be be big (over some thousands), if I don't specify I am going to run into many resize. This is really annoying as I'm not using a List which double its internal capacity every time but (purposefully) an home made collection which grows its internal capaciy linearly, hence lots of resize/copy will happen. 2. I thought of a format like <tag> <properties> ...... </properties> <content> ...... </content> </tag> but it's going to completely blow up the size of my XML file (lots of tag here!), which annoys me... whereas my format is 'compact'. What do you think of this concern? Show quote "Martin Honnen" <mahotr***@yahoo.de> wrote in message news:%235Bnn56vGHA.4436@TK2MSFTNGP06.phx.gbl... > > > Lloyd Dupont wrote: > > >> As the user could put whatever (s)he wants in the properties dictionary >> (s)he could as well create a key named 'count', therefore the 'count' >> atribute will be present twice in the tag. >> >> It's not a problem for my reader (which expect a first count followed by >> any kind of attribute) but it might be for other people wanting to >> consume my XML documents. > > Any XML parser/XML API can find the count of stuff elements by > parsing/counting the child stuff elements so I am not sure it is necessary > to have an attribute giving that count value. > As for trying to have two attributes of the name 'count', that is not > allowed in XML and breaks well-formedness rules. Also attributes of XML > elements are not ordered. > > I am also not sure how with Dictionary<string, object> any object you can > have in there fits in an XML attribute value. > > -- > > Martin Honnen --- MVP XML > http://JavaScript.FAQTs.com/ You may run into an issue with deserializing your distionary since the values
are of the type "Object" Writing them to an xml stream won't be a problem since you could just call ToString on all of the items, but reading them might be because you don't know what type they are. Could you take an approach like this? <stuff> <property name="propx" value="valx" type="System.String"/> <property name="propy" value="valy" type="System.Int32"/> <property name="propz" value="valz" type="System.DateTime"/> .... </stuff> You can get the types when serializing by wither using object.GetType() and then deserialize to the correct type. Also, when you think about it, there really isn't a point is hacing the count attribute there. When you deserialize this document, you can build your dictionary as the appropriate nosed are read without having to worry about the document's state as a whole. Also, the document's structure can now be defined discretely through DTD or XmlSxhema, which means you can create your xmlReader with an XmlSchema instance so that your input is validated while it is being read into your application. Show quote "Lloyd Dupont" wrote: > I have a class which looks like that: > > class Stuff > { > Dictionary<string, object> properties; > List<Stuff> children; > } > > I'm writing a home made XML 'serialization'. > I quote that, because it's not serialization, I'm writing the XML writer > myself (without System.Reflection). > > > I'm using a shema like that: > <stuff count=2 key1="value1" key2="value2" key3="value3"> > <stuf> > ......... > </stuff> > <stuf> > ......... > </stuff> > </stuff> > > where count = children.Count > and key1,2,3 are the keys in the properties dictionary and value1,2,3 their > values. > > properties is to be filled by the user with whatever (s)he wants. > > > Now my problem is: > ============== > > As the user could put whatever (s)he wants in the properties dictionary > (s)he could as well create a key named 'count', therefore the 'count' > atribute will be present twice in the tag. > > It's not a problem for my reader (which expect a first count followed by any > kind of attribute) but it might be for other people wanting to consume my > XML documents. > > What do you think? > > it's actually much easier this way... > (particularly because this sample output is far from the whole story) > > > Thanks for your remark, but this problem is already solved ;-)
Show quote "David Jessee" <DavidJes***@discussions.microsoft.com> wrote in message news:43260337-DE2D-494D-A717-FA44C9AE9D62@microsoft.com... > You may run into an issue with deserializing your distionary since the > values > are of the type "Object" > Writing them to an xml stream won't be a problem since you could just call > ToString on all of the items, but reading them might be because you don't > know what type they are. > > Could you take an approach like this? > > <stuff> > <property name="propx" value="valx" type="System.String"/> > <property name="propy" value="valy" type="System.Int32"/> > <property name="propz" value="valz" type="System.DateTime"/> > ... > </stuff> > > You can get the types when serializing by wither using object.GetType() > and > then deserialize to the correct type. Also, when you think about it, > there > really isn't a point is hacing the count attribute there. > When you deserialize this document, you can build your dictionary as the > appropriate nosed are read without having to worry about the document's > state > as a whole. Also, the document's structure can now be defined discretely > through DTD or XmlSxhema, which means you can create your xmlReader with > an > XmlSchema instance so that your input is validated while it is being read > into your application. > > > > "Lloyd Dupont" wrote: > >> I have a class which looks like that: >> >> class Stuff >> { >> Dictionary<string, object> properties; >> List<Stuff> children; >> } >> >> I'm writing a home made XML 'serialization'. >> I quote that, because it's not serialization, I'm writing the XML writer >> myself (without System.Reflection). >> >> >> I'm using a shema like that: >> <stuff count=2 key1="value1" key2="value2" key3="value3"> >> <stuf> >> ......... >> </stuff> >> <stuf> >> ......... >> </stuff> >> </stuff> >> >> where count = children.Count >> and key1,2,3 are the keys in the properties dictionary and value1,2,3 >> their >> values. >> >> properties is to be filled by the user with whatever (s)he wants. >> >> >> Now my problem is: >> ============== >> >> As the user could put whatever (s)he wants in the properties dictionary >> (s)he could as well create a key named 'count', therefore the 'count' >> atribute will be present twice in the tag. >> >> It's not a problem for my reader (which expect a first count followed by >> any >> kind of attribute) but it might be for other people wanting to consume my >> XML documents. >> >> What do you think? >> >> it's actually much easier this way... >> (particularly because this sample output is far from the whole story) >> >> >>  |
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