Jan 29, 2013, 11:08 PM
[FIXED] [2.2] ComboBox.IsEmpty Always Returns False on Postback
Hi,
The ComboBox's IsEmpty property returns false on postback even when no selection is made and nothing was entered.
Ext.Net 2.1.1
Test Case:
Without modifying EmptyValue (defaults to null), IsEmpty will only return true if Value is null:
Assuming that LoadPostData's Value being set to "" was correct, the problem can be fixed by overridding IsEmpty to use EmptyText in ComboBoxBase.cs:
The ComboBox's IsEmpty property returns false on postback even when no selection is made and nothing was entered.
Ext.Net 2.1.1
Test Case:
<%@ Page Language="C#" %>
<%@ Register Assembly="Ext.Net" Namespace="Ext.Net" TagPrefix="ext" %>
<script runat="server">
public class Person
{
public int ID { get; set; }
public string Name { get; set; }
}
protected void Page_Load(object sender, EventArgs e)
{
if (!X.IsAjaxRequest && !IsPostBack)
{
testStore.DataSource = new List<Person>
{
new Person(){ ID = 4, Name = "PHB"},
new Person(){ ID = 5, Name = "Alice"},
new Person(){ ID = 7, Name = "Dilbert"},
};
testStore.DataBind();
}
}
protected void btn_DirectClick(object sender, DirectEventArgs e)
{
if (testCombo.IsEmpty)
X.Msg.Alert("Combo Empty", "Combo Empty").Show();
else
X.Msg.Alert("Combo Not Empty", "Combo Not Empty").Show();
}
</script>
<!DOCTYPE html>
<html>
<head id="Head1" runat="server">
<title>Test</title>
</head>
<body>
<form id="Form1" runat="server">
<ext:ResourceManager ID="rsMan" runat="server" />
<ext:ComboBox ID="testCombo"
runat="server"
DisplayField="Name"
ValueField="ID"
QueryMode="Local"
FieldLabel="Test Combo">
<Store>
<ext:Store ID="testStore" runat="server">
<Model>
<ext:Model ID="testModel" runat="server">
<Fields>
<ext:ModelField Name="ID" />
<ext:ModelField Name="Name" />
</Fields>
</ext:Model>
</Model>
<Reader>
<ext:JsonReader />
</Reader>
</ext:Store>
</Store>
</ext:ComboBox>
<ext:Button runat="server" Text="Post" ID="btn" OnDirectClick="btn_DirectClick" />
</form>
</body>
</html>Without modifying EmptyValue (defaults to null), IsEmpty will only return true if Value is null:
[Description("Gets a value indicating whether the Value is equal to EmptyValue.")]
public virtual bool IsEmpty
{
get
{
return this.Value == null ? true : this.Value.Equals(this.EmptyValue);
}
}
[Meta]
[Category("5. Field")]
[DefaultValue(null)]
[Description("The fields null value.")]
public virtual object EmptyValue
{
get
{
return this.State.Get<object>("EmptyValue", null);
}
set
{
this.State.Set("EmptyValue", value);
}
} [Meta]
[ConfigOption]
[Category("6. TextField")]
[DefaultValue("")]
[Localizable(true)]
[Description("The default text to display in an empty field (defaults to null).")]
public virtual string EmptyText
{
get
{
return this.State.Get<string>("EmptyText", "");
}
set
{
this.State.Set("EmptyText", value);
}
} [Description("")]
protected override bool LoadPostData(string postDataKey, NameValueCollection postCollection)
{
this.HasLoadPostData = true;
string text = postCollection[this.UniqueName];
string state = postCollection[this.ValueHiddenName.IsNotEmpty() ? this.ValueHiddenName : ("_" + this.UniqueName + "_state")];
this.SuspendScripting();
this.RawValue = text;
this.Value = text; //<-------- This line will always result in an empty ComboBox Value to be "" not null
this.ResumeScripting();
if (state == null && text == null)
{
return false;
}
try
{
this.SuspendScripting();
if (!this.EmptyText.Equals(text) && text.IsNotEmpty())
{
List<ListItem> items = null;
if (this.SimpleSubmit)
{
string[] array = state.Split(new char[] { ',' });
items = new List<ListItem>(array.Length);
foreach (string item in array)
{
items.Add(new ListItem(item));
}
}
else if (state.IsNotEmpty())
{
items = ComboBoxBase.ParseSelectedItems(state);
}
bool fireEvent = false;
if (items == null)
{
items = new List<ListItem>
{
new ListItem(text)
};
}
foreach (ListItem item in items)
{
if (!this.SelectedItems.Contains(item))
{
fireEvent = true;
break;
}
}
this.SelectedItems.Clear();
this.SelectedItems.AddRange(items);
if (this.SelectedItems.Count > 0)
{
this.Value = this.SelectedItems[0].Value;
}
return fireEvent;
}
else
{
if (this.EmptyText.Equals(text) && this.SelectedItems.Count > 0)
{
this.SelectedItems.Clear();
return true;
}
}
}
catch
{
this.SuccessLoadPostData = false;
if (this.RethrowLoadPostDataException)
{
throw;
}
}
finally
{
this.ResumeScripting();
}
return false;
}Assuming that LoadPostData's Value being set to "" was correct, the problem can be fixed by overridding IsEmpty to use EmptyText in ComboBoxBase.cs:
public override bool IsEmpty
{
get
{
return this.Value == null ? true : this.Value.Equals(this.EmptyText);
}
}
Last edited by Daniil; Feb 07, 2013 at 11:40 AM.
Reason: [FIXED] [2.2]
