How to create an Empty XML file

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Guest

I have an application that must create a new, but empty, XML file on demand.
My original approach was to copy an existing "template XML file" into the new
XML file. I found that I needed to pass through each table in the newly
created XML file and delete each row. I'm wondering if there is a better
way. For example, I can programmatically create the XML file but the problem
with this method is that the creation process is within a program.

So is there a method that uses a schema to create an empty XML file. If
there is, where is it documented? If not, what is suggested?

TIA

Gus
 
Gus,

Is there a reason you don't want to do this from your program? An XML file
is nothing but a text file, so you can simply create a new file with an .xml
extension, and you're done.

Unless I'm missing something from your post.

-Altaf
 
Gus Gustafson said:
I have an application that must create a new, but empty, XML file on
demand.
My original approach was to copy an existing "template XML file" into the
new
XML file. I found that I needed to pass through each table in the newly
created XML file and delete each row. I'm wondering if there is a better
way. For example, I can programmatically create the XML file but the
problem
with this method is that the creation process is within a program.

So is there a method that uses a schema to create an empty XML file. If
there is, where is it documented? If not, what is suggested?
Click to expand...

You could save the empty XML file as a embedded resource in your app and
then retrieve it and write it out as necessary.
 
Although I appreciate that I can create the XML file from my program, I would
prefer to define (once) the structure of the XML file in some manner and then
use that definition to create an empty XML file (with all of its tables and
attributes, only without data).
 
You could use the FillSchema method of a dataAdapter to generate a dataset
with one empty table that has all the original table's schema information
intact. From there, you could use the dataset's WriteXMLSchema or WriteXML
methods to create the actual XML files you seek.
 
There are a variety of ways to attack this problem:

1. The template can be empty nodes, which you start populating.
2. The template can only have the important parent nodes, which you append
data to
3. You can use a DataSet format and add information that way and then
transform with XSLT and stream back out for the user
4. A schema, which is an XML file, can be transformed to become a document.

I do not know of an autogen for XML from a schema in .NET proper. I am sure
someone has solved this as a third party tool. Try sourceforge.net and see
if any open source implementations exist.

--
Gregory A. Beamer
MVP; MCP: +I, SE, SD, DBA

***********************************************
Think Outside the Box!
***********************************************
 
Hey, folks thanks for your thoughts. Here's what I came up with as a result
of your inputs.

1. I created an XSD file that defines the XML file. It is currently in a
directory that is relative to the location of the executable. I do like Jim's
idea (make it a resource) and I'm still thinking about it.

2. When I need to create a new instance of the XML file, I take the
following steps:

a. data_set = new DataSet ( ) ;
b. data_set.ReadXmlSchema ( XDS_path ) ;
c. directory = Path.GetDirectoryName ( XML_path ) ;
if ( ! Directory.Exists ( directory ) )
{
Directory.CreateDirectory ( directory ) ;
}
d. data_set.WriteXmlSchema ( XML_path ) ;

3. Massage the newly created XML file using ReadXml and WriteXml.

The only thing that I needed to remember (and forgot) was to check
table.Rows.Count before trying to perform

DataRow row = table.Rows [ 0 ] ;

Thought I'd pass it on.

Thanks for everyones help.

Regards,

Gus
 
One additional item.

When reading the XML file into a data set, use one of the ReadXML overloads
that includes the ReadXmlMode parameter set to ReadSchema. For example,

data_set.ReadXml (
path,
XmlReadMode.ReadSchema ) ;

Likewise, when writing to the XML file from the data set, use one of the
WriteXML overloads that includes the WriteXmlMode parameter set to
WriteSchema. For example,

data_set.WriteXml (
path,
XmlWriteMode.WriteSchema ) ;


Again, thanks to all for the help.

Gus
 
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