Error while inserting floating point value in textboxfor MVC - asp.net-mvc

Question

I have a strange problem, I have a model definied like this:
public class AddEventModel
{
[Required]
[DataType(DataType.Text)]
[Display(Name = "Nazwa wydarzenia")]
public string EventName { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Rodzaj")]
public string EventType { get; set; }
[Required]
[DataType(DataType.DateTime)]
[Display(Name = "Data")]
public System.DateTime EventDate { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Widocznosc")]
public string IsPublic { get; set; }
[DataType(DataType.Text)]
[Display(Name = "Minimalny wiek")]
public int MinimalAge { get; set; }
[Display(Name = "Cena")]
[DataType(DataType.Text)]
public decimal Payment { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Opis")]
public string Description { get; set; }
[Required]
[DataType(DataType.Text)]
[Display(Name = "Miasto")]
public string City { get; set; }
public SelectList EventTypeList { get; set; }
}
What is more i have a page writen in razor like this (i will post just part of it):
<div class="form-group">
#Html.LabelFor(m => m.EventName, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.TextBoxFor(m => m.EventName, new { #class = "form-control" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(m => m.EventType, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.DropDownListFor(m => m.EventType, Model.EventTypeList, new { #class = "form-control" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(m => m.EventDate, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.TextBoxFor(m => m.EventDate, new { #class = "form-control", id = "datepicker" })
</div>
<script type="text/javascript">
$(function () {
$('#datepicker').datetimepicker({
minDate: moment()
});
});
</script>
</div>
<div class="form-group">
#Html.LabelFor(m => m.IsPublic, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
<table>
<tr>
<td><label>#Html.RadioButtonFor(m => m.IsPublic, "Prywatne") Prywatne</label></td>
</tr>
<tr>
<td><label>#Html.RadioButtonFor(m => m.IsPublic, "Publiczne") Publiczne</label></td>
</tr>
</table>
</div>
</div>
<div class="form-group">
#Html.LabelFor(m => m.MinimalAge, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.TextBoxFor(m => m.MinimalAge, new { #class = "form-control" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(m => m.Payment, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.TextBoxFor(m => m.Payment, new { #class = "form-control" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(m => m.Description, new { #class = "col-md-2 control-label" })
<div class="col-md-10">
#Html.TextAreaFor(m => m.Description, new { #class = "form-control" })
</div>
</div>
</div>
Okay, so, when I am inserting my new event with a floating point number in field Cena/Payment im getting a strange error like this:
The ViewData item that has the key 'EventType' is of type 'System.String' but must be of type 'IEnumerable'.
It is pretty strange beacuse it is pointing on dropdownlist which is not connected with a Payment field. As I said, when I put a integer into Payment field - everything works fine.
Whats going on guys?
EDIT
Okey guys, i get it that i didnt reassing a SelectList in a post method. I fixed that already. However:
I want to understand why it was apearing only when i put a floating point number in a textbox
How to fix next problem: Value 'x.x' is not valid for Cena

Answer 1

The error is throw because the value of EventTypeList in
#Html.DropDownListFor(m => m.EventType, Model.EventTypeList, new { #class = "form-control" }
is null
This is happening because when you post back, ModelState is invalid and you return the view without re-assigning the SelectList (as you did in the GET method).
The reason ModelState is invalid is because the culture on the server does not accept the . (dot) character as a decimal separator (most likely it is a culture that uses , (comma) as the decimal separator). You need to change the culture in the web.config file, for example to <<globalization culture ="en-US" />