XML Writer stored results to string [duplicate] - c#

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Alternative ways to convert data table to customized XML
DataTable dt = new DataTable();
dt.Columns.Add(new DataColumn("Product_ID", Type.GetType("System.String")));
dt.Columns.Add(new DataColumn("Product_Name", Type.GetType("System.String")));
dt.Columns.Add(new DataColumn("product_Price", Type.GetType("System.Int32")));
fillRows("hello1", dt, "product1", 1111);
fillRows("hello2", dt, "product2", 2222);
fillRows("hello3", dt, "product3", 3333);
fillRows("hello4", dt, "product4", 4444);
var xmlColumnZero = dt.AsEnumerable().Select(col => col[0].ToString()).ToArray() ; // row 0 turnovermultiplieer
var xmlRowZero = dt.Columns;
string firstColumnHeader = dt.Columns[0].ToString();
// XmlDocument xmldoc = new XmlDocument();
XmlWriter writer = XmlWriter.Create("employees.xml");
writer.WriteStartDocument();
writer.WriteStartElement("Employees");
// XmlElement first = xmldoc.CreateElement("Order");
//xmldoc.AppendChild(first);
foreach (DataColumn dc in dt.Columns )
{
if (dc.ToString() == firstColumnHeader) continue;
string firstcol = dc.ToString();
writer.WriteStartElement(firstcol);
// XmlElement colRoot = xmldoc.CreateElement(firstcol);
//first.AppendChild(colRoot);
for (int i = 0 ; i <dt.Rows.Count && i< xmlColumnZero.Length ; i++)
{
string firstrow = xmlColumnZero[i];
string dtagaga = dt.Rows[i][dc].ToString();
writer.WriteElementString(firstrow, dtagaga);
// XmlElement rowRoot = xmldoc.CreateElement(firstrow, dtagaga);
//colRoot.AppendChild(rowRoot);
}
writer.WriteEndElement();
}
writer.WriteEndElement();
writer.WriteEndDocument();
I want the XMl to be stored into a string while i am creating XMLWriter.
Is there another way i can create xml out of the table
XML should look like
The xml writer method stores everything into an xml file in the program location. Would prefer a string to be saved
<Employees>
<Product_Name>
<hello1>product1</hello1>
hello2>product2</hello2>
hello3>product3</hello3>
hello4>product4</hello4>
</product_name>
<product_Price>
<hello1>1111</hello1>
hello2>2222</hello2>
hello3>3333</hello3>
hello4>4444</hello4>
</product_Price>
</Employees>

Just use overloaded method XmlWriter.Create(StringBuilder output) to create xml string. In this case all output will be written to StringBuilder instead of file:
StringBuilder builder = new StringBuilder();
XmlWriter writer = XmlWriter.Create(builder);
//... build xml here
string xml = builder.ToString();
Also you can write xml to MemoryStream with XmlWriter.Create(Stream output).
Stream stream = new MemoryStream();
XmlWriter writer = XmlWriter.Create(stream);
// ... build xml here
stream.Position = 0;
string xml = new StreamReader(stream).ReadToEnd();
UPDATE
Extension method below will generate your xml string. By default it uses first column as element names, but you can pass any column index for column with meta data. Also I use table name to generate "Employees" tag, so provide name when you create data table DataTable dt = new DataTable("Employees");.
public static string ToXml(this DataTable table, int metaIndex = 0)
{
XDocument xdoc = new XDocument(
new XElement(table.TableName,
from column in table.Columns.Cast<DataColumn>()
where column != table.Columns[metaIndex]
select new XElement(column.ColumnName,
from row in table.AsEnumerable()
select new XElement(row.Field<string>(metaIndex), row[column])
)
)
);
return xdoc.ToString();
}
Usage is very simple:
string xml = dt.ToXml();
Output:
<Employees>
<Product_Name>
<hello1>product1</hello1>
<hello2>product2</hello2>
<hello3>product3</hello3>
<hello4>product4</hello4>
</Product_Name>
<product_Price>
<hello1>111</hello1>
<hello2>222</hello2>
<hello3>333</hello3>
<hello4>444</hello4>
</product_Price>
</Employees>

Use a StringBuilder and create the XmlWriter using the StringBuilder instead of a file:
StringBuilder sb = new StringBuilder();
XmlWriter writer = XmlWriter.Create(sb);
writer.WriteStartDocument();
//...
writer.WriteEndDocument();
var myXmlString = sb.ToString(); //myXmlString will contain the XML

Instead of creating a file
XmlWriter writer = XmlWriter.Create("employees.xml");
You can use String stream
StringWriter sw = new StringWriter();
XmlWriter writer = XmlWriter.Create(sw);
...
...
// sw.ToString(); // string output

Related

Convert Comma separated string to XML using C#

I want to convert the string to XML.
I have a string like below. It contains the Programming language names.
string lang = "java,php,c#,asp.net,spring,hibernate";
I want to convert this string to XML formal like below:
<Languages>
<lang Name="java"/>
<lang Name="php"/>
<lang Name="c#"/>
<lang Name="asp.net"/>
<lang Name="spring"/>
<lang Name="hibernate"/>
</Languages>
I want to store this XML data in a variable to store later in a database.
It can also be done using Linq-to-XML:
using System.Xml.Linq; // required namespace
XDocument xmlDoc = new XDocument();
XElement xElm = new XElement("Languages",
from l in lang.Split(',')
select new XElement("lang", new XAttribute("Name", l)
)
);
xmlDoc.Add(xElm);
string lang = "java,php,c#,asp.net,spring,hibernate";
string[] langs = lang.Split(',');
XmlDocument document = new XmlDocument();
XmlElement root = document.CreateElement("Languages");
document.AppendChild(root);
for (int i = 0; i < langs.Length; i++)
{
XmlElement langElement = document.CreateElement("lang");
XmlAttribute nameAttr = document.CreateAttribute("Name");
nameAttr.Value = langs[i];
langElement.Attributes.Append(nameAttr);
root.AppendChild(langElement);
}
document.WriteTo(new XmlTextWriter(Console.Out) {
Formatting = Formatting.Indented
});
A short version of what you have done, using Linq and the string manipulation functions
var vales = lang.Split(','); //Splits the CSV
var xmlBody = vales.Select(v => string.Format("<lang Name=\"{0}\"/>",v));
var xml = string.Join(string.Empty, xmlBody); //Potentially add a new line as a seperator
xml = string.Format("<Languages>{0}</Languages>", xml);
The other option is to convert your csv into a model that implements ISerialize and then use the xml serializer. That is more code and not necessarily bad. If you would like to see an example, feel free to ask and I will post an example.
This is working,
class Program
{
static void Main(string[] args)
{
string lang = "java,php,c#,asp.net,spring,hibernate";
StringBuilder sb = new StringBuilder();
sb.AppendFormat("<Languages>");
foreach (string s in lang.Split(','))
{
sb.AppendFormat("<lang Name=\"{0}\"/>", s);
}
sb.AppendFormat("</Languages>");
Console.WriteLine(sb.ToString());
Console.ReadLine();
}
}

Remove white space from xml node not to attribute value

From below imput xml, i should get output xml as described.
Input Xml
<BPSResponse> <Response> <Code>804</Code> <Text>TagID value is not genuine.</Text> </Response> </BPSResponse>
Output Xml
<BPSResponse><Response><Code>804</Code><Text>TagID value is not genuine.</Text></Response></BPSResponse>
I am creating xml by XElement.
var bpsResponseXml = new XElement("BPSResponse");
for (int i = 0; i < bpsResponseStatusCodes.Count; i++)
{
var bpsResponse = BPSResponseDictionary.GetBPSResponse(bpsResponseStatusCodes[i]);
bpsResponseXml.Add(new XElement("Response",
new XElement("Code", bpsResponse.Code),
new XElement("Text", bpsResponse.Text)));
}
var outPutXml = bpsResponseXml.Value;
I want output xml as formatted above.
var doc = new System.Xml.XmlDocument()
{
PreserveWhitespace = false
};
doc.LoadXml(xmlString);
string flat = doc.OuterXml;
I just have to disable the formatting while converting to string. Below is sample code.
var bpsResponseXml = new XElement("BPSResponse");
bpsResponseXml.Add(new XElement("Response",
new XElement("Code", "804"),
new XElement("Text", "TagID value is not genuine")));
var outPutXml = bpsResponseXml.ToString(System.Xml.Linq.SaveOptions.DisableFormatting);

Appending an existing XML file with XmlWriter

I've used the following code to create an XML file:
XmlWriterSettings xmlWriterSettings = new XmlWriterSettings();
xmlWriterSettings.Indent = true;
xmlWriterSettings.NewLineOnAttributes = true;
using (XmlWriter xmlWriter = XmlWriter.Create("Test.xml", xmlWriterSettings))
{
xmlWriter.WriteStartDocument();
xmlWriter.WriteStartElement("School");
xmlWriter.WriteEndElement();
xmlWriter.WriteEndDocument();
xmlWriter.Close();
}
I need to insert nodes dynamically creating the following structure:
<?xml version="1.0" encoding="utf-8"?>
<School />
<Student>
<FirstName>David</FirstName>
<LastName>Smith</LastName>
</Student>
...
<Teacher>
<FirstName>David</FirstName>
<LastName>Smith</LastName>
</Teacher>
...
</School>
How can I do it? The values of "FirstName" and "LastName" should be read from the keyboard and the values ​​can be entered at any time, of course under existing.
you can use Linq Xml
XDocument doc = XDocument.Load(xmlFilePath);
XElement school = doc.Element("School");
school.Add(new XElement("Student",
new XElement("FirstName", "David"),
new XElement("LastName", "Smith")));
doc.Save(xmlFilePath);
Edit
if you want to add Element to Existing <Student>, just add an Attribute before
school.add(new XElement("Student",
new XAttribute("ID", "ID_Value"),
new XElement("FirstName", "David"),
new XElement("LastName", "Smith")));
Then you can add further Details to the Existing <Student> by search -> get -> add
XElement particularStudent = doc.Element("School").Elements("Student")
.Where(student => student.Attribute("ID").Value == "SearchID")
.FirstOrDefault();
if(particularStudent != null)
particularStudent.Add(new XElement("<NewElementName>","<Value>");
finally I succeeded :)
if (!File.Exists("Test.xml"))
{
XmlWriterSettings xmlWriterSettings = new XmlWriterSettings();
xmlWriterSettings.Indent = true;
xmlWriterSettings.NewLineOnAttributes = true;
using (XmlWriter xmlWriter = XmlWriter.Create("Test.xml", xmlWriterSettings))
{
xmlWriter.WriteStartDocument();
xmlWriter.WriteStartElement("School");
xmlWriter.WriteStartElement("Student");
xmlWriter.WriteElementString("FirstName", firstName);
xmlWriter.WriteElementString("LastName", lastName);
xmlWriter.WriteEndElement();
xmlWriter.WriteEndElement();
xmlWriter.WriteEndDocument();
xmlWriter.Flush();
xmlWriter.Close();
}
}
else
{
XDocument xDocument = XDocument.Load("Test.xml");
XElement root= xDocument.Element("School");
IEnumerable<XElement> rows = root.Descendants("Student");
XElement firstRow= rows.First();
firstRow.AddBeforeSelf(
new XElement("Student",
new XElement("FirstName", firstName),
new XElement("LastName", lastName)));
xDocument.Save("Test.xml");
}
Let me give you a suggestion. When you creating your xml file, give an unique id to your students like this:
// to store the id variable, if you create more than one student you can increase it
count = 0;
xmlWriter.WriteStartElement("School");
xmlWriter.WriteAttributeString("ID",count.ToString());
xmlWriter.WriteEndElement();
Then when you need to add information to this student you can get ID,Firstname and Lastname and you can edit your XML file with LINQ to XML like this:
int id = Convert.ToInt32(txtStudentId.Text);
XDocument xDoc = XDocument.Load("Test.xml");
XElement student = xDoc.Descendants("Student").Where(x => (string) x.Attribute("ID") == id).FirstOrDefault();
if (student != null)
{
string firstName = txtFirstName.Text;
string lastName = txtLastName.Text;
XElement first = new XElement("FirstName", firstName);
XElement last = new XElement("LastName", lastName);
student.Add(first);
student.Add(last);
xDoc.Save("Test.xml");
}
I have a suggestion for the next time:
string nameFile = "Test.xml";
bool newFile = false;
if (!File.Exists(nameFile))
{
newFile = true;
XmlWriterSettings xmlWriterSettings = new XmlWriterSettings();
xmlWriterSettings.Indent = true;
xmlWriterSettings.NewLineOnAttributes = true;
xmlWriter.WriteStartDocument();
xmlWriter.WriteStartElement("School");
xmlWriter = XmlWriter.Create("Test.xml", xmlWriterSettings))
}
else
{
doc = new XmlDocument();
doc.Load(nameFile);
// Create a XPathNavigator
// You can go where you want to add
// In this case it is just after last child of the roor
XPathNavigator navigator = doc.CreateNavigator();
navigator.MoveToChild("School", "");
xmlWriter = navigator.AppendChild();
}
// From here you can work only with xmlWriter,
// One will point on a file and the other on the stream of xmlDocument
// So you will need to save the document in the second choise
xmlWriter.WriteStartElement("Student");
xmlWriter.WriteElementString("FirstName", firstName);
xmlWriter.WriteElementString("LastName", lastName);
xmlWriter.WriteEndElement();
// End document / close or save.
if (newFile)
xmlWriter.WriteEndDocument();
xmlWriter.Close();
if (!newFile)
doc.Save(nameFile);
It should work. :)
I know you asked for XmlWriter, but I believe you can achieve this using less code with XDocument. Here is my solution:
var filePath = "path/XmlFile.xml";
var xmlDoc = XDocument.Load(filePath);
var parentElement = new XElement("Student");
var firstNameElement = new XElement("FirstName", firstNameVariable);
var lastNameElement = new XElement("LastName", lastNameVariable);
parentElement.Add(firstNameElement);
parentElement.Add(lastNameElement);
var rootElement = xmlDoc.Element("School");
rootElement?.Add(parentElement);
xmlDoc.save();
This is based on the following XML structure and will append at ... :
<School>
<Student>
<FirstName>John</FirstName>
<LastName>Johnson</LastName>
</Student>
...
</School>
Hope this helps!

Get actual Column name from XML

I have a problem with this XML. In our system we are using XML from DataSet (ds.GetXml()) and send it to our Silverlight application as a string. From there we read the XML with the following:
StringReader stream = new StringReader(XmlData);
XmlReader reader = XmlReader.Create(stream);
XDocument myDoc = new XDocument();
myDoc = XDocument.Load(reader);
The problem: Some times column names are changed, example: If a column name starts with a numeric number then it will convert it.
"_x0033_column" original column name was "3column"
Is it possible to get the original column name from the XML?
The XML
<NewDataSet>
<Table>
<CheckboxCol>0</CheckboxCol>
<Kunde>1</Kunde>
<Ort_x0020_Postfach />
<erfasst_x0020_von>MasterMind</erfasst_x0020_von>
<Buchhaltungsnummer>1</Buchhaltungsnummer>
<Kreditlimit>0.0000</Kreditlimit>
<_x0033_STT_Inaktiv>Nein</_x0033_STT_Inaktiv>
<_x0033_STT_Status>Interessent</_x0033_STT_Status>
<Zahlungsbedingungen>10 : 10 Tage Netto</Zahlungsbedingungen>
</Table>
<Table>
<CheckboxCol>0</CheckboxCol>
<Kunde>3</Kunde>
<Ort_x0020_Postfach />
<erfasst_x0020_von>MasterMind</erfasst_x0020_von>
<Buchhaltungsnummer>3</Buchhaltungsnummer>
<Kreditlimit>0.0000</Kreditlimit>
<_x0033_STT_Inaktiv>Nein</_x0033_STT_Inaktiv>
<_x0033_STT_Status>Kunde</_x0033_STT_Status>
<Zahlungsbedingungen>10 : 10 Tage Netto</Zahlungsbedingungen>
</Table>
<NewDataSet>
My current Code
public SLDataTable(string XmlData, Dictionary<string, string> ColumnDict)
{
ColumnDefination = ColumnDict;
foreach (var Item in ColumnDefination)
{
Columns.Add(new SLDataColumn() { ColumnName = Item.Key.ToString().Trim(), DataType = GetNullableType(GetColumnType(Item.Value.ToString())) });
}
StringReader stream = new StringReader(XmlData);
XmlReader reader = XmlReader.Create(stream);
XDocument myDoc = new XDocument();
myDoc = XDocument.Parse(XmlData);
if (myDoc != null && myDoc.Elements().Count() > 0 && myDoc.Element("NewDataSet").Elements().Count() > 0)
{
int columnCount = myDoc.Element("NewDataSet").Element("Table").Elements().Count();
int rowCount = myDoc.Element("NewDataSet").Elements().Count();
string ElmentColumnName = string.Empty;
foreach (XElement element in myDoc.Element("NewDataSet").Elements())
{
var row = new SLDataRow(this);
foreach (XElement ele in element.Elements())
{
ElmentColumnName = ele.Name.ToString().Replace("_x0020_", " ").Replace("_x0028_", " (").Replace("_x0029_", ") ");
row[ElmentColumnName] = ConvertValue(ElmentColumnName, ele.Value);
}
Rows.Add(row);
}
}
}

Loading XML String into datatable

string parseData= "<TEST xmlns:dt=\"urn:schemas-microsoft-com:datatypes\"><A dt:dt=\"string\">10</A><B dt:dt=\"string\">20</B></TEST>";
DataSet ds = new DataSet("Whatev");
TextReader txtReader = new StringReader(parseData);
XmlReader reader = new XmlTextReader(txtReader);
ds.ReadXml(reader);
DataTable ad = new DataTable("newT");
ad.ReadXml(reader);
For this I am getting empty table in ad, and three tables in ds.
What I am expecting is,
one table with two columns A and B, and one row with values 10 and 20.
What am I doing wrong?
You're simply not using it correctly. There's a number of problems:
You are reading from the same stream twice. In the first pass, the stream pointer is at the end of the stream. You attempt to read from it again when it's already at the end so nothing else is read. Either read into your data set or into your data table, not both. Or, at least seek back to the beginning of the stream if you really want to.
Your XML is not in the correct format. It has to be in the format:
<SomeRoot>
<TableName>
<ColumnName>ColumnValue</ColumnName>
</TableName>
<TableName>
<ColumnName>AnotherColumnValue</ColumnName>
</TableName>
</SomeRoot>
You won't be able to use that method with any arbitrary XML.
Your tables do not have a schema set. You need to either read in a schema or set it up beforehand.
var table = new DataTable("TEST");
table.Columns.Add("A", typeof(string));
table.Columns.Add("B", typeof(string));
table.ReadXml(xmlReader);
Try this instead:
var xmlStr = #"<Root>
<TEST>
<A>10</A>
<B>20</B>
</TEST>
</Root>";
var table = new DataTable("TEST");
table.Columns.Add("A", typeof(string));
table.Columns.Add("B", typeof(string));
table.ReadXml(new StringReader(xmlStr));
If you decide to parse that XML yourself, LINQ can help you out here.
public static DataTable AsDataTable(XElement root, string tableName, IDictionary<string, Type> typeMapping)
{
var table = new DataTable(tableName);
// set up the schema based on the first row
XNamespace dt = "urn:schemas-microsoft-com:datatypes";
var columns =
(from e in root.Element(tableName).Elements()
let typeName = (string)e.Element(dt + "dt")
let type = typeMapping.ContainsKey(typeName ?? "") ? typeMapping[typeName] : typeof(string)
select new DataColumn(e.Name.LocalName, type)).ToArray();
table.Columns.AddRange(columns);
// add the rows
foreach (var rowElement in root.Elements(tableName))
{
var row = table.NewRow();
foreach (var column in columns)
{
var colElement = rowElement.Element(column.ColumnName);
if (colElement != null)
row[column.ColumnName] = Convert.ChangeType((string)colElement, column.DataType);
}
table.Rows.Add(row);
}
return table;
}
Then to use it:
var xmlStr = #"<Root>
<TEST xmlns:dt=""urn:schemas-microsoft-com:datatypes"">
<A dt:dt=""string"">10</A>
<B dt:dt=""string"">20</B>
</TEST>
</Root>";
var root = XElement.Parse(xmlStr);
var mapping = new Dictionary<string, Type>
{
{ "string", typeof(string) },
};
var table = AsDataTable(root, "TEST", mapping);
There probably is a better way to get the associated .NET type for a datatype but I don't know how to do that at the moment, I'll update if I find that out.

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