Question with Linq on XML,At least one object must implement IComparable - c#

string studentsXML =
#"<Students>
<Student>
<Name>Toni</Name>
<Age>21</Age>
<University>Yale</University>
<Semester>6</Semester>
<GPA>3.5</GPA>
</Student>
<Student>
<Name>Carla</Name>
<Age>17</Age>
<University>Yale</University>
<Semester>1</Semester>
<GPA>3.8</GPA>
</Student>
<Student>
<Name>Leyla</Name>
<Age>19</Age>
<University>Beijing Tech</University>
<Semester>3</Semester>
<GPA>3.0</GPA>
</Student>
<Student>
<Name>Frank</Name>
<Age>25</Age>
<University>Beijing Tech</University>
<Semester>10</Semester>
<GPA>2.0</GPA>
</Student>
<Student>
<Name>Ken</Name>
<Age>29</Age>
<University>Beijing Tech</University>
<Semester>10</Semester>
<GPA>4.0</GPA>
</Student>
</Students>";
**Above is the XML code and I'm trying to sort it in order of age using linq so it should be able to display name and age in order at the end.
Code below is showing error. Would appreciate it if someone could give me input on this.
I'm actually still learning right now and was trying out stuff but obviously it is not working. **
XDocument studentsXdoc1 = new XDocument();
studentsXdoc1 = XDocument.Parse(studentsXML);
var testing = from student in studentsXdoc1.Descendants("Student")
orderby student.Element("Age")
select new
{
Name = student.Element("Name"),
Age = student.Element("Age")
};
foreach(var i in testing)
{
Console.WriteLine(i);
}
Console.ReadKey();

Just add .Value to student.Element("Age") to get the value of the element
var testing = from student in studentsXdoc1.Descendants("Student")
orderby int.Parse(student.Element("Age").Value)
select new
{
Name = student.Element("Name").Value,
Age = student.Element("Age").Value
};
The value of age needs to be parsed when ordering by age.

Related

XPath string to select a specific node with specific value c#

I want to select a node where inner text of cat is 'PG' using XPath
<?xml version="1.0" encoding="utf-8"?>
<Students>
<student>
<name>Talha</name>
<cat>PG</cat>
</student>
<student>
<name>irfan</name>
<cat>UG</cat>
</student>
<student>
<name>Ali</name>
<cat>PG</cat>
</student>
<student>
<name>Umer</name>
<cat>UG</cat>
</student>
</Students>
Code which I tried is this
XmlElement xmldoc = (XmlElement)doc.DocumentElement
.SelectSingleNode("/Students/student/*[*[local-name()='cat']='PG']");
To select all the student nodes which sub-elements cat have the value 'PG' use this XPath expression
/Students/student[cat='PG']
To only get the first one use
/Students/student[cat='PG'][1]
So in the syntax of C# use
XmlElement xmldoc = (XmlElement)doc.DocumentElement.SelectSingleNode("/Students/student[cat='PG'][1]");

Parsing XML Element Once

I have a peace of xml which I need to gather information off.
<response>
<students>
<student>
<educationalinstitutionname>Test One</educationalinstitutionname>
<academicqualificationtype>TestLevel One</academicqualificationtype>
<starttime>22/02/06</starttime>
<endtime>19/08/10</endtime>
<grade>A</grade>
</student>
<student>
<educationalinstitutionname>Test One</educationalinstitutionname>
<academicqualificationtype>TestLevel Two</academicqualificationtype>
<starttime>22/02/06</starttime>
<endtime>19/08/10</endtime>
<grade>B</grade>
</student>
<student>
<educationalinstitutionname>Test Two</educationalinstitutionname>
<academicqualificationtype>TestLevel Two</academicqualificationtype>
<starttime>22/02/06</starttime>
<endtime>19/08/10</endtime>
<grade>C</grade>
</student>
<student>
<educationalinstitutionname>Test Two</educationalinstitutionname>
<academicqualificationtype>TestLevel Three</academicqualificationtype>
<starttime>22/02/06</starttime>
<endtime>19/08/10</endtime>
<grade>D</grade>
</student>
</students>
The issue which I am having is that I need to parse the educationalinstitutionname once if it the same but gather the academicqualificationtype, starttime, endtime and grade for everything that it appears under the same educationalinstitutionname node.
XmlNodeList WordXMLNodeLists = XmlResponceDoc.SelectNodes("/response/students/student");
string GetDetaisl = string.Empty;
foreach (XmlNode GradeItem in WordXMLNodeLists)
{
string GetStartDate = EducationElement.SelectNodes("/response/students/student/starttime")[0].InnerText;
string GetEndDate = EducationElement.SelectNodes("/response/students/student/endtime")[0].InnerText;
string GetEstablishmentName = EducationElement.GetElementsByTagName("educationalinstitutionname")[0].InnerText;
string GetGrade = EducationElement.SelectNodes("/response/students/student/grade")[0].InnerText;
GetDetaisl = string.Concat(GetStartDate, " ", GetEndDate, " ", GetEstablishmentName);
if (GetDetaisl.Length == GetEstablishmentName.Length)
{
string GetGrades = GetGrade;
GetEducationNodeDate.Add(GetGrades);
}
else
{
GetEducationNodeDate.Add(GetDetaisl);
continue;
}
}
The issue which I am finding is that I cannot seem to loop through the name once and gather all the information in the document under that name for the establishment. Thanks for any help which you can provide
It isn't very clear what you're trying to achieve specifically. I assumed that basically you want value of most of nodes within <student> tag :
XmlNodeList WordXMLNodeLists = XmlResponceDoc.SelectNodes("/response/students/student");
foreach (XmlNode GradeItem in WordXMLNodeLists)
{
string GetStartDate = GradeItem.SelectSingleNode("./starttime").InnerText;
string GetEndDate = GradeItem.SelectSingleNode("./endtime").InnerText;
string GetEstablishmentName = GradeItem.SelectSingleNode("./educationalinstitutionname").InnerText;
string GetGrade = GradeItem.SelectSingleNode("./grade").InnerText;
//do something with data gathered above
}

SelectSingleNode Node InnerText property not correct

I am attempting to get the value of a specific node for each parent element found.
In the example I want to return each students First Name.
Instead I am getting the first elements name in each instance. The InnerText of a Student is correct but the InnerText of FirstName is always Alex.
var xml = #"<School>
<Students>
<Student>
<FirstName>Alex</FirstName>
<LastName>Smith</LastName>
<Grade>11</Grade>
</Student>
<Student>
<FirstName>Joanne</FirstName>
<LastName>Robins</LastName>
<Grade>12</Grade>
</Student>
<Student>
<FirstName>Steve</FirstName>
<LastName>Baker</LastName>
<Grade>11</Grade>
</Student>
</Students>
<Teachers>
<Teacher>
<FirstName>George</FirstName>
<LastName>Roberts</LastName>
<Grade>11</Grade>
</Teacher>
<Teacher>
<FirstName>Amanda</FirstName>
<LastName>Walker</LastName>
<Grade>12</Grade>
</Teacher>
<Teacher>
<FirstName>Tracey</FirstName>
<LastName>Smith</LastName>
<Grade>12</Grade>
</Teacher>
</Teachers>
</School>";
var doc = new XmlDocument();
doc.LoadXml(xml);
var resourceTypeNodes = doc.GetElementsByTagName("Student");
var resourceTypesIterator = resourceTypeNodes.GetEnumerator();
while (resourceTypesIterator != null && resourceTypesIterator.MoveNext())
{
var resourceTypeNode = resourceTypesIterator.Current as XmlNode;
var typeNameElement = resourceTypeNode.SelectSingleNode("//FirstName");
Console.WriteLine(resourceTypeNode.InnerXml);
Console.WriteLine(typeNameElement.InnerText);
}
This is the output of the above code.
<FirstName>Alex</FirstName><LastName>Smith</LastName><Grade>11</Grade>
Alex
<FirstName>Joanne</FirstName><LastName>Robins</LastName><Grade>12</Grade>
Alex
<FirstName>Steve</FirstName><LastName>Baker</LastName><Grade>11</Grade>
Alex
What am I missing?
Because you're using //FirstName XPath expression, that will always return first node from root, it doesn't matter if you invoke on children. Just change this:
var typeNameElement = resourceTypeNode.SelectSingleNode("//FirstName");
To this:
var typeNameElement = resourceTypeNode.SelectSingleNode("FirstName");
Moreover is there any specific reason you're manually using IEnumerator? You may simplify your code with foreach:
foreach (XmlNode resourceTypeNode in doc.GetElementsByTagName("Student"))
{
var typeNameElement = resourceTypeNode.SelectSingleNode("FirstName");
Console.WriteLine(resourceTypeNode.InnerXml);
Console.WriteLine(typeNameElement.InnerText);
}

How to get values of XElements from more than one Descendants in Windows Phone 8

How do I get XElements values from more than one Descendants
See my XML Document:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<WithoutGroup>
<StudentId>21</StudentId>
<StudentName>Photo</StudentName>
<Image>dshdsdhshdsghs</Image>
<WithoutGroup>
<group>
<groupId>471</groupId>
<groupName>General </groupName>
<Student>
<StudentId>85</StudentId>
<StudentName>Action</StudentName>
<Image>qwerxcxcxcbvbxcx</Image>
</Student>
<Student>
<StudentId>27</StudentId>
<StudentName>Docs</StudentName>
<Image>xcxncbxncsds</Image>
</Student>
</group>
</root>
I want "STUDENT NAME" and "STUDENT ID", how do I put condition?
Any help would be greatly appreciated!!
Here is code:
XDocument doc = XDocument.Parse(e.Result);
List<STUDENT> list = new List<STUDENT>();
list = (from query in doc.Descendants("WithoutGroup")
select new STUDENT
{
stdId = Convert.ToInt64(query.Element("StudentId").Value),
stdName = query.Element("StudentName").Value,
Icon = getImage(query.Element("Image").Value),
}).ToList();
If you're sure that <StudentID> always followed by <StudentName>, you can select all <StudentID> descendants and use XElement.NextNode to get corresponding <StudnetName> :
list = (from id in doc.Descendants("StudentId")
select new STUDENT
{
stdId = (Int64)id,
stdName = (string)(XElement)id.NextNode
}).ToList();

Unable to extract value from XDocument using xpath

I have a simple xml of users. I have a StudentId, I just need to get the student name from the xml on the basis of studentid. Seems to be simple but I am unable to get it done using xpath.
Here's the xml:
<Students>
<Student>
<StudentId>1</StudentId>
<StudentName>Mad</StudentName>
</Student>
<Student>
<StudentId>2</StudentId>
<StudentName>Cad</StudentName>
</Student>
</Students>
Here's my code:
XDocument xmldoc = XDocument.Load(Server.MapPath("~/xmlsample.xml"));
string StudentId = "2"; // id to be selected
var username = xmldoc.XPathSelectElement("Students/Student/StudentName").Value;// Not sure how to use where condition here
You just need to filter by studentId. Should be:
var username = xmldoc.XPathSelectElement(String.Format("Students/Student[StudentId={0}]/StudentName", StudentId)).Value;

Categories