xPath query

[TR]

I'm trying the select a element based on values of two attributes. In the
Xml doc i need to look at an attribute minVal and maxVal. if the Value I'm
passing in in the xPath is greate than min "and" less than max, I'll want
to pull all the attributes of that element.

Is this possible with xPath? I'm able to easily query 1 attribute, but not
two.

Thanks

TR

[Martin Honnen]

TR wrote:

I'm trying the select a element based on values of two attributes. In
the Xml doc i need to look at an attribute minVal and maxVal. if the
Value I'm passing in in the xPath is greate than min "and" less than
max, I'll want to pull all the attributes of that element.

//element[$value > @minValue and $value < @maxValue]/@*

--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[TR]

Hello Martin,
Thanks for the reply. I forget to mention 1 thing. I values need to be
greater-than or equal to and less-than or equal to.

I missed the equal to part.

the syntax you provided worked for evaluating two the attributes.

Tr

TR wrote:

I'm trying the select a element based on values of two attributes.
In the Xml doc i need to look at an attribute minVal and maxVal. if
the Value I'm passing in in the xPath is greate than min "and" less
than max, I'll want to pull all the attributes of that element.

//element[$value > @minValue and $value < @maxValue]/@*

[Cerebrus]

Hi TR,

XPath supports the operators >= and <= as well. You can use these in
the expression that Martin provided to meet your requirement.

//element[$value >= @minValue and $value <= @maxValue]/@*

HTH,

Regards,

Cerebrus.

[TR]

Hello Cerebrus,
Thanks for the follow-up. here are some details and results....
Below is a snippet of the Xml I'm trying to select. If a match is found,
I need to use all attribs of the Node

<Node>
<Formgroups>
<Formula MinAmt="0" MaxAmt="51" Group="0" PercentValue="0"> </Formula>
<Formula MinAmt="51" MaxAmt="192" Group="51.00" PercentValue="10">
</Formula>
<Formula MinAmt="192" MaxAmt="620" Group="98.00" PercentValue="15">
</Formula>
<Formula MinAmt="620" MaxAmt="1409" Group="306.80" PercentValue="25">
</Formula>
</Formgroups>
</Node>
EX:: $Value=53 Result: NodeList.item(0) should be: <Formula MinAmt="51"
MaxAmt="192" Group="51.00" PercentValue="10"> </Formula>
Current syntax

/Node/Formgroups/Formula[@MinAmt >= $Value] == Works

/Node/Formgroups/Formula[@MinAmt >= $Value and(@MaxAmt <= $Value)] ===
Fails

/Node/Formgroups/Formula[@MinAmt >= $Value and @MaxAmt <= $Value] ===Fails

Also, I tried the syntax you include at the end of the attribute eval,
" /@* ". Not sure what that does, but I put it in and still no luck. The
xPath expression was valid, just nothing populated in my NodeList
Thanks again!!! Appreciate the assistance.

Hi TR,

XPath supports the operators >= and <= as well. You can use these in
the expression that Martin provided to meet your requirement.

//element[$value >= @minValue and $value <= @maxValue]/@*

HTH,

Regards,

Cerebrus.

[Martin Honnen]

TR wrote:

Below is a snippet of the Xml I'm trying to select. If a match is found,
I need to use all attribs of the Node

<Node>
<Formgroups>
<Formula MinAmt="0" MaxAmt="51" Group="0" PercentValue="0"> </Formula>
<Formula MinAmt="51" MaxAmt="192" Group="51.00" PercentValue="10">
</Formula>
<Formula MinAmt="192" MaxAmt="620" Group="98.00" PercentValue="15">
</Formula>
<Formula MinAmt="620" MaxAmt="1409" Group="306.80"
PercentValue="25"> </Formula>
</Formgroups>
</Node>

Here is one example

public static void Test (double value, string url) {
XPathDocument xmlDocument = new XPathDocument(url);
string xPathExpression =
String.Format(
CultureInfo.InvariantCulture,
"Node/Formgroups/Formula[{0} >= @MinAmt and {0} <= @MaxAmt]",
value
);
XPathNavigator xPathNavigator = xmlDocument.CreateNavigator();
XPathNodeIterator nodeIterator =
xPathNavigator.Select(xPathExpression);
while (nodeIterator.MoveNext()) {
Console.WriteLine("Found {0}, attributes are:",
nodeIterator.Current.Name);
if (nodeIterator.Current.MoveToFirstAttribute()) {
do {
Console.WriteLine("Attribute name: {0}, attribute value:
{1}", nodeIterator.Current.Name, nodeIterator.Current.Value);
}
while (nodeIterator.Current.MoveToNextAttribute());
nodeIterator.Current.MoveToParent();
}
Console.WriteLine();
}
}

you could call that as e.g.

Test(53.6, @"example.xml");

and then the output is

Found Formula, attributes are:
Attribute name: MinAmt, attribute value: 51
Attribute name: MaxAmt, attribute value: 192
Attribute name: Group, attribute value: 51.00
Attribute name: PercentValue, attribute value: 10
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[Cerebrus]

Hi TR,

1. The " /@* " at the end selects all the attributes of all the
returned nodes. Martin probably added that in because of your original
statement : "I'll want to pull all the attributes of that element."

2. Well, I don't know if we're on the same page, but in your example :
(Using sample $Value of 53 on your sample XML)

As expected, only the first one of your 3 XPath expressions will work.
Reasons are below...
The first expression selects the 3rd and 4th node.
The second and 3rd expression won't select anything. This is because
you're making a logical mistake here. The 3rd expression should be :
/Node/Formgroups/Formula[@MinAmt >= $Value and $Value <= @MaxAmt].

^^^^^^^^^
This is because you need to select a value that is greater than the
MinAmt and *less than* the MaxAmt. The expression you've written can be
interpreted as MaxAmt <= Value <= MinAmt, which is impossible in your
XML file. So, it does not select anything.

When written properly, your XPath should select the 3rd and 4th node.
(of the sample XML you gave)

Hope this helps,

Regards,

Cerebrus.

[Cerebrus]

Hi TR,

1. The " /@* " at the end selects all the attributes of all the
returned nodes. Martin probably added that in because of your original
statement : "I'll want to pull all the attributes of that element."
2. Well, I don't know if we're on the same page, but in your example :
(Using sample $Value of 53 on your sample XML)
As expected, only the first one of your 3 XPath expressions will work.
Reasons are below...
The first expression selects the 3rd and 4th node.
The second and 3rd expression won't select anything. This is because
you're making a logical mistake here. The 3rd expression should be :

/Node/Formgroups/Formula[@MinAmt >= $Value and $Value <= @MaxAmt].

This is because you need to select a value that is greater than the
MinAmt and *less than* the MaxAmt. The expression you've written can be

interpreted as MaxAmt <= Value <= MinAmt, which is impossible in your
XML file. So, it does not select anything.
When written properly, your XPath should select the 3rd and 4th node.
(of the sample XML you gave) ,

Edit: And not the 2nd node.
Hope this helps,
Regards,
Cerebrus.

[TR]

Hello Cerebrus, Martin,
I appreciate the assistance.

The syntax provided partially works. You made it very clear on the logic
error.

I tried the syntax provided, but something still doen't work correctly.
If I provide a value of say, 195, the expression returns record 4 from the
example previously. It should have returned records 3 and 4.
Thanks!!!!
TR

Hi TR,

1. The " /@* " at the end selects all the attributes of all the
returned nodes. Martin probably added that in because of your original
statement : "I'll want to pull all the attributes of that element."

2. Well, I don't know if we're on the same page, but in your example :
(Using sample $Value of 53 on your sample XML)

As expected, only the first one of your 3 XPath expressions will work.
Reasons are below...
The first expression selects the 3rd and 4th node.
The second and 3rd expression won't select anything. This is because
you're making a logical mistake here. The 3rd expression should be :
/Node/Formgroups/Formula[@MinAmt >= $Value and $Value <= @MaxAmt].

This is because you need to select a value that is greater than the
MinAmt and *less than* the MaxAmt. The expression you've written can
be

interpreted as MaxAmt <= Value <= MinAmt, which is impossible in your
XML file. So, it does not select anything.

When written properly, your XPath should select the 3rd and 4th node.
(of the sample XML you gave) ,

Edit: And not the 2nd node.

Hope this helps,

Regards,

Cerebrus.

[Martin Honnen]

TR wrote:

I tried the syntax provided, but something still doen't work correctly.
If I provide a value of say, 195, the expression returns record 4 from
the example previously. It should have returned records 3 and 4.

Why? Greater than or equal to the minimum and less than or equal to the
maximum was your reqirement in your first two posts.
The example provided in the third post was

<Node>
<Formgroups>
<Formula MinAmt="0" MaxAmt="51" Group="0" PercentValue="0"> </Formula>
<Formula MinAmt="51" MaxAmt="192" Group="51.00" PercentValue="10">
</Formula>
<Formula MinAmt="192" MaxAmt="620" Group="98.00"
PercentValue="15"> </Formula>
<Formula MinAmt="620" MaxAmt="1409" Group="306.80"
PercentValue="25"> </Formula>
</Formgroups>
</Node>

For a value of 195 there is only one element

<Formula MinAmt="192" MaxAmt="620" Group="98.00" PercentValue="15">
</Formula>

matching the requirement. Unless you are changing the requirements with
every post.
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[TR]

Hello Martin,

Oops, my bad. It is correct. If you noticed it was very early in the morning.

Thansk for your help...
TR

TR wrote:

I tried the syntax provided, but something still doen't work
correctly. If I provide a value of say, 195, the expression returns
record 4 from the example previously. It should have returned
records 3 and 4.

Why? Greater than or equal to the minimum and less than or equal to
the
maximum was your reqirement in your first two posts.
The example provided in the third post was
<Node>
<Formgroups>
<Formula MinAmt="0" MaxAmt="51" Group="0" PercentValue="0">
</Formula>
<Formula MinAmt="51" MaxAmt="192" Group="51.00"
PercentValue="10">
</Formula>
<Formula MinAmt="192" MaxAmt="620" Group="98.00"
PercentValue="15"> </Formula>
<Formula MinAmt="620" MaxAmt="1409" Group="306.80"
PercentValue="25"> </Formula>
</Formgroups>
</Node>
For a value of 195 there is only one element

<Formula MinAmt="192" MaxAmt="620" Group="98.00"
PercentValue="15"> </Formula>

matching the requirement. Unless you are changing the requirements
with every post.