My name
is
Jon Skeet

Type inference failure with LINQ select

I have a template TimeSpan in MVC.

View

@model TimeSpan?
@{
    var id = "id" + Guid.NewGuid().ToString().Substring(0, 5);
    string format = (string)(this.ViewData["format"] ?? @"hh\:mm\:ss");

    IEnumerable<SelectListItem> listValues;

    if (this.Model.HasValue)
    {
        listValues = from x in Enumerable.Range(0, 96)
                     .Select(x => new TimeSpan(9000000000 * x))
                     .Select(x => new SelectListItem {Selected = true, Value = x.ToString(), 
                                                       Text = x.ToString(format) })
    }
    else
    {
        listValues = from x in Enumerable.Range(0, 96)
                     select new SelectListItem { Value = x.ToString(), 
                                                 Text = x.ToString(format) };   
    }

}
<div class="field-small">
    @Html.DropDownListFor(x => x, listValues, new { id = id})
</div>
<script type="text/javascript"">
    $("#@id")
        .turnAutoComplete();
</script>

but have exception

The type of the expression in the select clause is incorrect. Type inference failed in the call to 'Select'.

and

A query body must end with a select clause or a group clause

Line error

listValues = from x in Enumerable.Range(0, 96)
                 .Select(x => new TimeSpan(9000000000 * x))
                 .Select(x => new SelectListItem { Selected = true, Value = x.ToString(),
                                                   Text = x.ToString(format) })

I do not know about identifying what's wrong with my line

You're trying to mix query expression syntax with regular method calls, and you've ended up with something that isn't a complete query expression. You could use:

listValues = from x in Enumerable.Range(0, 96)
             let ts = new TimeSpan(9000000000 * x)
             select new SelectListItem {
                 Selected = true,
                 Value = ts.ToString(),
                 Text = ts.ToString(format)
             };

Or just:

listValues = Enumerable.Range(0, 96)
                 .Select(x => new TimeSpan(9000000000 * x))
                 .Select(x => new SelectListItem {
                     Selected = true,
                     Value = x.ToString(),
                     Text = x.ToString(format)
                 });

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