is it possible to convert Int32 to String?

Question

Is it possible to convert Int32 to string?

I am having difficulties with this line of the code, where I am trying to convert Int32 to string.

var listOrder = daa.OrderByDescending(i => i.Times).ToList().Convert.ToString().OrderByDescending(jtSorting);

i.Times is Int32 and I have to pass jSorting parameter which is string.

I get this error when I compile:

"Does not contain a defination for 'Convert' and no extension method 'Convert' accepting a first argument of type"

Full controller code for your inspection:

public JsonResult TopPlayedInVenueList1(string name = "", string ArtistName = "", int jtStartIndex = 0, int jtPageSize = 0, string jtSorting = null)
    {
        try
        {
            if (Request.IsAuthenticated == true)
            {
                string Path = @"C:\\5Newwithdate-records.xls";
                OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source= '" + 
                                                            Path + "';Extended Properties=" + (char)34 + 
                                                            "Excel 8.0;IMEX=1;" + (char)34 + "");
                OleDbDataAdapter da = new OleDbDataAdapter("select * from [Sheet1$]", con);

                System.Data.DataTable data = new System.Data.DataTable();
                da.Fill(data);
                con.Close();

                List<TopPlayed> daa = new List<TopPlayed>();
                foreach (DataRow p in data.Rows)
                {
                    TopPlayed top = new TopPlayed()
                    {
                        TrackID = Convert.ToInt32(p.Field<double>("TrackID")),
                        TrackName = p.Field<string>("TrackName"),
                        ArtistName = p.Field<string>("ArtistName"),
                        Times = Convert.ToInt32(p.Field<double>("Times"))
                    };

                    daa.Add(top);
                }

                ///// var newlist = daa.OrderByDescending(i => i.Times).ToList().GetRange(jtStartIndex, jtPageSize);

                var newlist = daa.AsQueryable().OrderByDescending(jtSorting).OrderByDescending(i => i.Times).ToList();

                return Json(new { Result = "OK", Records = newlist, TotalRecordCount = daa.Count });

View Code of jTable Datatable:

 $(document).ready(function () {
    $('#TopPlayedInVenueContainer1').jtable({

        title: 'NSM Biling Report List',
        paging: true,
        pageSize: 100,
        sorting: true,
      //  defaultSorting: 'Times ASC',

        actions: {
            listAction: '@Url.Action("TopPlayedInVenueList1")'

        },
        fields: {
            TrackID: {
                title: 'Track ID',
                key: true,
                create: false,
                edit: false,
                resize: false,
                tooltip: 'Track Name'
            },
            TrackName: {
                title: 'Track Name',
                key: true,
                create: false,
                edit: false,
                resize: false,
                tooltip: 'Track Name'
            },
            ArtistName: {
                title: 'Artist Name',
                key: true,
                create: false,
                edit: false,
                resize: false,
                tooltip: 'Track Name'
            },
            Times: {
                title: 'Times',
                tooltip: 'Artist Name'
            }
        }
    });

    $('#LoadRecordsButton').click(function (e) {
        e.preventDefault();
        $('#TopPlayedInVenueContainer1').jtable('load', {
            name: $('#name').val(),
            ArtistName: $('#ArtistName').val()
        });
    });

    //Load all records when page is first shown
    $('#LoadRecordsButton').click();
});

OrderByExtensions

namespace NSM.BackOffice.Controllers
{
public static class OrderByExtensions
{
    public static IQueryable<T> OrderBy<T>(this IQueryable<T> source, string ordering)
    {
        var type = typeof(T);
        var property = type.GetProperty(ordering);
        var parameter = Expression.Parameter(type, "p");
        var propertyAccess = Expression.MakeMemberAccess(parameter, property);
        var orderByExp = Expression.Lambda(propertyAccess, parameter);
        MethodCallExpression resultExp = Expression.Call(typeof(Queryable), "OrderBy", new Type[] { type, property.PropertyType }, source.Expression, Expression.Quote(orderByExp));
        return source.Provider.CreateQuery<T>(resultExp);
    }

    public static IQueryable<T> OrderByDescending<T>(this IQueryable<T> source, string ordering)
    {
        var type = typeof(T);
        var property = type.GetProperty(ordering);
        var parameter = Expression.Parameter(type, "p");
        var propertyAccess = Expression.MakeMemberAccess(parameter, property);
        var orderByExp = Expression.Lambda(propertyAccess, parameter);
        MethodCallExpression resultExp = Expression.Call(typeof(Queryable), "OrderByDescending", new Type[] { type, property.PropertyType }, source.Expression, Expression.Quote(orderByExp));
        return source.Provider.CreateQuery<T>(resultExp);
    }
}

}

I am fresh with c# so if you could please let me know a workout to get this to work. thanks in advance.

Answer 1

You can call ToString during projection in Enumerable.Select

var listOrder = daa.OrderByDescending(i => i.Times).Select(c=>c.Times.ToString()).ToList();

Answer 2

This part:

OrderByDescending(i => i.Times).ToList().Convert.ToString()

looks very strange. Convert here is not a property and not a method call. You might probably want this instead:

OrderByDescending(i => i.Times).ToList().Select(x => x.ToString())

Update. Following up discussion in comments - here is how to use the extension method implemented here. Declare a static class somewhere in the project like this:

public static class OrderByExtensions
{
    public static IQueryable<T> OrderBy<T>(this IQueryable<T> source, string ordering) {
        var type = typeof(T);
        var property = type.GetProperty(ordering);
        var parameter = Expression.Parameter(type, "p");
        var propertyAccess = Expression.MakeMemberAccess(parameter, property);
        var orderByExp = Expression.Lambda(propertyAccess, parameter);
        MethodCallExpression resultExp = Expression.Call(typeof(Queryable), "OrderBy", new Type[] { type, property.PropertyType }, source.Expression, Expression.Quote(orderByExp));
        return source.Provider.CreateQuery<T>(resultExp);
    }

    public static IQueryable<T> OrderByDescending<T>(this IQueryable<T> source, string ordering) {
        var type = typeof(T);
        var property = type.GetProperty(ordering);
        var parameter = Expression.Parameter(type, "p");
        var propertyAccess = Expression.MakeMemberAccess(parameter, property);
        var orderByExp = Expression.Lambda(propertyAccess, parameter);
        MethodCallExpression resultExp = Expression.Call(typeof(Queryable), "OrderByDescending", new Type[] { type, property.PropertyType }, source.Expression, Expression.Quote(orderByExp));
        return source.Provider.CreateQuery<T>(resultExp);
    }
}

Make sure this class is visible inside the TopPlayedInVenueList1, if not - use using to make so. After that you should be able to do this with any IQueryable<>:

.OrderByDescending(jtSorting);

Answer 3

You jsSorting parameter is for sorting datatables, not IEnumerables: Try this:

data.DefaultView.Sort = jsSorting;   

Answer 4

You are trying to convert your list object to a string:

var listOrder = daa.OrderByDescending(i => i.Times).ToList().Convert.ToString();

What you may want (and I don't know your requirements is):

var listOrder = daa.OrderByDescending(i => i.Times).Select(i => i.Times.ToString()).ToList();

Which would give you a list of strings.

---

As per your comment, if the technique noted is beyond you, you could do this (and this might be fine if there are a limited number of columns that you want to sort by):

List<TopPlayed> sorted;

switch (jtSorting)
{
   case "Times":
      sorted = daa.OrderByDescending(i => i.Times).ToList();
      break;
   case "Other":
      sorted = daa.OrderByDescending(i => i.Other).ToList();
      break;
    default:
      //Oops.  Do something appropriate here.
}

// etc.

Answer 5

Pretty much everything in C# inherits from object, which has a ToString() method. Not everything provides a particularly useful implementation (some things just print their type name, particularly collections) but Int32 does. Therefore, i.Times.ToString() will give you the string version.

Answer 6

If you use Linq

daa.OrderByDescending(i => i.Times.ToString())
daa.OrderByDescending(i => (string)i.Times)

If you use Linq on EF

daa.OrderByDescending(i => SqlFunctions.StringFormat((double?)i.Times))