I have a datatable in which no of columns is dynamic. I need a list with header name and value.I found a question similar to this question.
enter link description here
But can not getting desired output.
Output with this solution
In Dynamic View :
In Result View
I m using this Code for Convert to dynamic object :
public static List<dynamic> ToDynamic(this DataTable dt)
{
var dynamicDt = new List<dynamic>();
foreach (DataRow row in dt.Rows)
{
dynamic dyn = new ExpandoObject();
foreach (DataColumn column in dt.Columns)
{
var dic = (IDictionary<string, object>)dyn;
dic[column.ColumnName] = row[column];
}
dynamicDt.Add(dyn);
}
return dynamicDt;
}
Need a output like that :-
How can i achieve this?
You can achieve that by modifying the ToDynamic method you are using. The original method is:
public static class DataTableExtensions
{
public static List<dynamic> ToDynamic(this DataTable dt)
{
var dynamicDt = new List<dynamic>();
foreach (DataRow row in dt.Rows)
{
dynamic dyn = new ExpandoObject();
dynamicDt.Add(dyn);
//--------- change from here
foreach (DataColumn column in dt.Columns)
{
var dic = (IDictionary<string, object>)dyn;
dic[column.ColumnName] = row[column];
}
//--------- change up to here
}
return dynamicDt;
}
}
Replace the lines between the "change" comments into:
foreach (var columnName in new[] {"A", "B", "C", "D", "E"} )
{
var dic = (IDictionary<string, object>)dyn;
if(dt.Columns.Contains(columnName))
dic[columnName] = row[dt.Columns[columnName]];
else
dic[columnName] = 0;
}
That's assuming you need column names A to E, adjust as appropriate if you need more columns.
Related
I have a DataTable that I would like to convert into dictionary in C# for my project. I can use the traditional way of programming to achieve the goal but it is not as elegant as using linq/lambda. I tried to use Lambda but I got stuck in how to flatten multiple rows into 1.
I have a mock DataTable for testing purpose.
static DataTable GetData()
{
DataTable table = new DataTable();
table.Columns.Add("Field1", typeof(string));
table.Columns.Add("Field2", typeof(string));
table.Rows.Add("A", "A1");
table.Rows.Add("A", "A2");
table.Rows.Add("B", "B1");
table.Rows.Add("A", "A3");
table.Rows.Add("C", "C1");
table.Rows.Add("D", "D1");
table.Rows.Add("A", "A5");
return table;
}
My traditional way to convert it to Dictionary is:
Dictionary<string, ArrayList> t = new Dictionary<string, ArrayList>();
foreach (DataRow r in GetData().Rows)
{
string k = (string)r["Field1"];
string v = (string)r["Field2"];
if (!t.Keys.Contains(r["Field1"]))
{
t.Add(k, new ArrayList());
}
if (t.Values == null)
{
t[k] = new ArrayList();
}
t[k].Add(v);
}
How do I achieve the same thing with Linq?
I have tried:
var res = GetData()
.AsEnumerable()
.GroupBy(row => row.Field<string>("Field1"))
.Select(grp => grp.First());
This only gives me the first occurrence of the item. I am stuck.
Please help.
Actually, you don't want to convert it to a Dictionary, but to a Lookup. Here's an example:
var lookup = GetData().AsEnumerable()
.ToLookup(r => r.Field<string>("Field1"), r => r.Field<string>("Field2"));
foreach (var grouping in lookup)
{
Console.WriteLine(grouping.Key + ": " + String.Join(", ", grouping));
}
Output:
A: A1, A2, A3, A5
B: B1
C: C1
D: D1
Get Data from Datatable as Dictionary without Linq/Lambda
DataTable dataTable = GetData();
var data = new List<Dictionary<string, object>>();
foreach (DataRow dataTableRow in dataTable.Rows)
{
var dic = new Dictionary<string, object>();
foreach (DataColumn tableColumn in dataTable.Columns)
{
dic.Add(tableColumn.ColumnName, dataTableRow[tableColumn]);
}
data.Add(dic);
}
you can get a Collection:
var res = GetData()
.AsEnumerable()
.Select(grp => new KeyValuePair<string, string>(grp[0].ToString(), grp[1].ToString()));
I am new to C# and gone through lot of questions in Stackoverflow.com and didn't find the solution for my requirement. So finally posting here.
My requirement is to create the dynamic properties from datatable column names and set the values to dynamic properties from datatable. and finally bind the data to gridview.
So I decided to follow below steps to achieve this functionality( kindly Correct me If I am wrong)
my datatable contains 26 rows and 10 columns of data
Create a Class A
Add dynamic properties to A from datatable(column names)
Set values to properties of A
Make class A to List of A
Bind List of A to GridView
I have done the below steps
1.
[Serializable]
public class A
{
public A()
{
}
}
2 & 3.
DataTable dt = getData();
dynamic expando = new ExpandoObject();
foreach (DataRow row in dt.Rows)
{
foreach (DataColumn col in dt.Columns)
{
var expandoDict = expando as IDictionary<String, Object>;
if (expandoDict.ContainsKey(col.ToString()))
expandoDict[col.ToString()] = row[col.ColumnName].ToString();
else
expandoDict.Add(col.ToString(), row[col.ColumnName].ToString());
}
}
After executing the above for loop, "expando" object contains only last row of datatable.
Can you please help me how to fix the steps 2 to 5.
From what I understand, this code may be more what you are looking for. This should get the data into the expandoList for you. You will then need to handle the binding to the GridView.
DataTable dt = getData();
List<dynamic> expandoList = new List<dynamic>();
foreach (DataRow row in dt.Rows)
{
//create a new ExpandoObject() at each row
var expandoDict = new ExpandoObject() as IDictionary<String, Object>;
foreach (DataColumn col in dt.Columns)
{
//put every column of this row into the new dictionary
expandoDict.Add(col.ToString(), row[col.ColumnName].ToString());
}
//add this "row" to the list
expandoList.Add(expandoDict);
}
Here's an extension method that would convert your datatable to list of Dynamic objects:
public static class DataTableExtension
{
public static IEnumerable<dynamic> AsDynamicEnumerable(this DataTable table)
{
// Validate argument here..
return table.AsEnumerable().Select(row => new DynamicRow(row));
}
private sealed class DynamicRow : DynamicObject
{
private readonly DataRow _row;
internal DynamicRow(DataRow row) { _row = row; }
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
var retVal = _row.Table.Columns.Contains(binder.Name);
result = retVal ? _row[binder.Name] : null;
return retVal;
}
}
}
Usage: IEnumerable<dynamic> result = getData().AsEnumerable();
I am getting data from data table and convert it into json like this:
public object DataTableToJSON(DataTable table)
{
var list = new List<Dictionary<string, object>>();
foreach (DataRow row in table.Rows)
{
var dict = new Dictionary<string, object>();
foreach (DataColumn col in table.Columns)
{
dict.Add(col.ColumnName,row[col]);
}
list.Add(dict);
}
JavaScriptSerializer serializer = new JavaScriptSerializer();
return serializer.Serialize(list);
}
But while iterating through JSON data , this method is giving key names as column1,column2...(as datatable don't have any column name)
I want the column names should be something like 1,2...
How can I achieve this using above method ?
Change
dict.Add(col.ColumnName,row[col]);
to
var keyName = string.IsNullOrEmpty(col.ColumnName)
? col.Ordinal + 1
: col.ColumnName;
dict.Add(keyName, row[col]);
When you have a column name this will be taken and we you don't have one you will take the index + 1 of the column.
You can build in a Counter
public object DataTableToJSON(DataTable table)
{
var list = new List<Dictionary<string, object>>();
foreach (DataRow row in table.Rows)
{
var dict = new Dictionary<string, object>();
var counter = 1;
foreach (DataColumn col in table.Columns)
{
dict.Add(counter.ToString(),row[col]);
counter++;
}
list.Add(dict);
}
JavaScriptSerializer serializer = new JavaScriptSerializer();
return serializer.Serialize(list);
}
But keep in mind: double keynames are not allowed.
The Ordinal property of the DataColumn object will give you the position of the column, so you can tweak your code to use this.
public object DataTableToJSON(DataTable table)
{
var list = new List<Dictionary<string, object>>();
foreach (DataRow row in table.Rows)
{
var dict = new Dictionary<string, object>();
foreach (DataColumn col in table.Columns)
{
dict.Add((col.Ordinal+1).ToString(),row[col]) ;
}
list.Add(dict);
}
JavaScriptSerializer serializer = new JavaScriptSerializer();
return serializer.Serialize(list);
}
I am here today trying to work out how I can do this. I have the code below to look through each column in a DataRow, but how can I access the key AND value? I want to assign it to a dictionary in the class but I can't seem to get both of them, the only way I can get anything is by calling:
var columnValue = playerDataRow[column];
Here is the full thing:
using (var mysqlConnection = Sirius.GetServer().GetDatabaseManager().GetConnection())
{
mysqlConnection.SetQuery("SELECT * FROM `users` WHERE `auth_ticket` = #authTicket LIMIT 1");
mysqlConnection.AddParameter("authTicket", authTicket);
var playerDataTable = mysqlConnection.GetTable();
foreach (DataRow playerDataRow in playerDataTable.Rows)
{
foreach (DataColumn column in playerDataTable.Columns)
{
var columnValue = playerDataRow[column];
}
}
}
foreach (DataRow playerDataRow in playerDataTable.Rows)
{
var myDic = new Dictionary<string, object>();
foreach (DataColumn column in playerDataTable.Columns)
{
myDic.Add(column.ColumnName, playerDataRow[column]);
}
}
the variable column will be the key and the value will be columnValue
looks that you only want one row of output - perhaps for this specific user based on auth_ticket
here is an example of how to get all values for this row into a Dictionary of strings (I'm converting all data to strings by the way just for this example)
var htRowValues = new Dictionary<string,string>();
using (var mysqlConnection = Sirius.GetServer().GetDatabaseManager().GetConnection())
{
mysqlConnection.SetQuery("SELECT * FROM `users` WHERE `auth_ticket` = #authTicket LIMIT 1");
mysqlConnection.AddParameter("authTicket", authTicket);
var playerDataTable = mysqlConnection.GetTable();
foreach (DataRow playerDataRow in playerDataTable.Rows)
{
foreach (DataColumn column in playerDataTable.Columns)
{
var columnValue = playerDataRow[column];
htRowValues[column.ColumnName]=System.Convert.ToString(columnValue);
}
}
}
now you have all column values in the dictionary for this one row of data.
I have a strongly typed class PersonExport. I initially get data into a DataTable and call the following method on the DataTable to convert it to List<PersonExport>:
public static List<T> ConvertToList<T>(DataTable dt, out string message)
{
message = string.Empty;
var list = new List<T>();
try
{
var columnNames = dt.Columns.Cast<DataColumn>()
.Select(c => c.ColumnName)
.ToList();
var properties = typeof(T).GetProperties();
list = dt.AsEnumerable().Select(row =>
{
var objT = Activator.CreateInstance<T>();
foreach (var pro in properties)
{
if (columnNames.Contains(pro.Name))
{
var value = row[pro.Name];
var typeName = value.GetType().FullName;
if (typeName == "MySql.Data.Types.MySqlDateTime")
{
var mySqlDateTime = (MySqlDateTime) value;
if (mySqlDateTime.IsValidDateTime)
{
value = Convert.ToDateTime(mySqlDateTime.ToString());
pro.SetValue(objT, value, null);
}
}
else
{
pro.SetValue(objT, row.IsNull(pro.Name) ? null : value, null);
}
}
}
return objT;
}).ToList();
}
catch (Exception ex)
{
message = (ex.InnerException != null) ? ex.InnerException.Message : ex.Message;
}
return list;
}
However, once I start removing columns from the DataTable returned, it no longer works because the columns in the DataTable don't match up with the properties in the PersonExport list.
I am eventually using the exported list here to export to excel, but it is not working since I have modified by DataTable and it can't Deserialize into a List<PersonExport>:
//Trying to get data into List<object>
List<object> persons = GetPersonExport(query, out message);
var exportData = new Dictionary<string, List<object>> { { "xldata", persons} };
//Deserialize to List<object> to export
var persons = JsonConvert.DeserializeObject<List<object>>(args["xldata"]);
The above line just returns a List of empty objects.
A few things got me thinking, but I am wondering what might be the best approach. I am using the EPPLUS library to export data to excel and it has the option of hiding columns, so would it be better to just export the whole object and hide columns you don't want, this way you avoid the anonymous type or what I can do is still get the whole object, but then convert it to a DataTable and then remove the columns? Thoughts?
All that you want is:
public IEnumerable<object> GetListOfObject()
{
foreach (var prod in TenMostExpensiveProducts().Tables[0].AsEnumerable())
{
yield return prod;
}
}
Or:
TenMostExpensiveProducts().Tables[0].AsEnumerable().Select (x => x).ToList<object>()
But you can get it work more elegant via linq like this:
from prod in TenMostExpensiveProducts().Tables[0].AsEnumerable()
where prod.Field<decimal>("UnitPrice") > 62.500M
select prod
Or like this (AsDynamic is called directly on DataSet):
TenMostExpensiveProducts().AsDynamic().Where (x => x.UnitPrice > 62.500M)
I prefer the last approach while is is the most flexible.
P.S.: Don't forget to connect System.Data.DataSetExtensions.dll reference
List<Dictionary<string, object>> rows = new List<Dictionary<string, object>>();
Dictionary<string, object> row;
foreach (DataRow dr in dt.Rows)
{
row = new Dictionary<string, object>();
foreach (DataColumn col in dt.Columns)
{
row.Add(col.ColumnName, dr[col]);
}
rows.Add(row);
}
StringBuilder sbRes = new StringBuilder();
jSon.Serialize(rows, sbRes);
ret = sbRes.ToString();