Import XML file into dataset

[Thomas Lischetzki]

Hello all together,

I have a little problem importing the following xml file into a dataset.

<?xml version="1.0" standalone="yes"?>
<logfile version = "0.1.001" >
<log date = "01.01.2005" time = "12:01:59" username = "Mueller" level =
"Info" message = "2">
<data order="1" caption="Original Value">60</data>
<data order="2" caption="Changed Value">80</data>
</log>
</logfile>

If I load the xml file in Visual Studio and looks at the data page I see 3
data tables.

1. logfile
2. log
3. data

If I choose the table 'log' it shows all information which are stored in the
tag 'log'.
Now I can expand a datarow and gets a link 'log data'.
If I click this link I get a new table with the information stored in the
tags 'data'.

That's fine, but how can I get access to the information within my code?
Hope you understand my problem and can help me.

Best regards
Thomas

[Cor Ligthert]

Thomas,

And XML dataset contains only elements. You have an XML document.
That you can only import in a dataset by reading it looping while using the
xmlnodereader to get attribute by attribute to set those in the dataset
elements (items).

I hope this gives an idea

Cor

[Thomas Lischetzki]

Hello Cor,

Hmm Visual Studio displays the XML file in a dataset with 2 layers (don't
know how to describe it better).
The first layer is a table which contains all information from the tag
'log'.
That means I have a table which contains rows like this one (according to my
example):

01.01.2005 12:01:59 Mueller Info 2

This rows have a plus, so I can expand it.
If I expand the row, I get a link to the second layer or better a second
table which contains the information of the tag 'data'.
The problem is that I don't have access to the second layer within my code.
I get the first layer (table) if I use the readXml-method of the dataset but
not the second layer (table).

Hope you understand what I mean.

Best regards
Thomas

[Cor Ligthert]

Thomas,

You can read it as dataset.

To show it, you can use the designer or this simple method.
\\\
System.Data.DataSet ds = new System.Data.DataSet();
ds.ReadXml("XMLFile1.xml");
this.dataGrid1.DataSource = ds;
this.dataGrid1.Expand(-1);
///

I hope this helps?

Cor

[Thomas Lischetzki]

Hello Cor,

that is not my problem.
I know that the designer shows me the XML file as a dataset.
You can see in my posting sent 24.02.2005 12:04, what my problem with this
representation is.
I need to get access to the secon layer and the information stored in the
'data' tag.

Best regards
Thomas

[Cor Ligthert]

Thomas,

That was why I showed this sample, when I add this
\\\
System.Data.DataSet ds = new System.Data.DataSet();
ds.ReadXml("XMLFile1.xml");
this.dataGrid1.DataSource = ds;
this.dataGrid1.Expand(-1);
this.textBox1.DataBindings.Add("Text",ds.Tables[1],"username");
///

Than I see "Mueller" in the textbox on the form.

It has an other effect that I don't like however it is because of this
sample because the field name what is than

ds.Tables["log"]["username"]

I was expecting you understood that.

I hope this helps?

Cor

[Thomas Lischetzki]

Hello Cor,

ok so I get access to the information stored in the tag 'log'.
I understood your example, but I don't get access to the information stored
in the tag 'data', because this information are stored in another table I
think or a table with a filter?!?
That is my main problem.

Thanks already for your time.

Best regards
Thomas

[Cor Ligthert]

Thomas,

Did you try my sample,

I get with this in the datagrid exactly what I expected.
(I see now that my too quick typed datafield was wrong however the method
stays the same)
{
System.Data.DataSet ds = new System.Data.DataSet();
ds.ReadXml("XMLFile1.xml");
ds.Tables["data"].Rows[0]["caption"] = "Hello I am there";
this.dataGrid1.DataSource = ds;
this.dataGrid1.Expand(-1);
}

I hope this helps?

Cor

[Thomas Lischetzki]

Hi Cor,

yes, your example shows me the XML file in a dataset like the designer does.
If I access the table 'data' with this code line:

ds.Tables["data"].Rows[0]["caption"] = "Hello I am there";

it works fine, but I don't have a relation to the related datarow in the
table 'log', did I?
The dataset in your example also shows me the link to the table 'data' if I
expand a datarow in the table 'log'.
But I can't access this filtered view of the table 'data'.

Best regards
Thomas

[Thomas Lischetzki]

Hi Cor,

yes, your example shows me the XML file in a dataset like the designer does.
If I access the table 'data' with this code line:

ds.Tables["data"].Rows[0]["caption"] = "Hello I am there";

it works fine, but I don't have a relation to the related datarow in the
table 'log', did I?
The dataset in your example also shows me the link to the table 'data' if I
expand a datarow in the table 'log'.
But I can't access this filtered view of the table 'data'.

Best regards
Thomas

[Cor Ligthert]

Thomas,

You mean this one, that is just playing with the relations.
\\\\
System.Data.DataSet ds = new System.Data.DataSet();
ds.ReadXml("XMLFile1.xml");
ds.Tables["data"].Rows[0]["caption"] = "Hello I am there";
ds.Tables["log"].ChildRelations[0].ChildTable.Rows[1]["caption"] = "I too";
this.dataGrid1.DataSource = ds;
this.dataGrid1.Expand(-1);
///

I hope it becomes clearer?

Cor

[Thomas Lischetzki]

Hi Cor,

many thanks to you.

The following sample code delivers me the needed information:

System.Data.DataSet ds = new System.Data.DataSet();
ds.ReadXml("log_2-2005.xml");

foreach (DataRow dr in ds.Tables["log"].Rows)
{
System.Windows.Forms.MessageBox.Show(dr["level"].ToString() + ", " +
dr["message"].ToString());
DataRow[] childs = dr.GetChildRows("log_data");
foreach(DataRow dr2 in childs)
{
System.Windows.Forms.MessageBox.Show(dr2["data_text"].ToString());
}
}

Thanks for the spent time in my problem.
I think now I understand the dataset much better.

Best regards
Thomas