Check If Combobox Value Is Empty

Check if combobox value is empty

if (string.IsNullOrEmpty(comboBox1.Text)) or if (comboBox1.SelectedIndex == -1)

Is there a way to check if comboBox Items are empty? C#

You can use comboBox1.Items.Count to count the number of comboboxes in the list:

if (comboBox1.Items.Count == 0)
{
    MessageBox.Show("no items in comboBox")
}

Checking if one combobox is empty and the other one isn't

You can use ListIndex

Example 1

Handling it together.

If ComboBox5.ListIndex = -1 Or ComboBox6.ListIndex = -1 Then
    MsgBox "Select both Year and Month"
Else
    '
    ' ~~> Do what you want
    '
End If

Example 2

Handling it separately

If ComboBox5.ListIndex = -1 Then
    MsgBox "Select Year"
    Exit Sub
End If

If ComboBox6.ListIndex = -1 Then
    MsgBox "Select Month"
    Exit Sub
End If

'
'~~> Do what you want
'

Note

If you want to use .Value then use it like this

If Len(Trim(ComboBox5.Value)) = 0 Then

End If

How to check multiple combo-box value is Empty or Not

Try to use linq and a recursion:

var isAnyEmpty = ScanForControls<ComboBox>(this)
   .Where(x => x.SelectedIndex < 0)
   .Any();

if (isAnyEmpty)
    MessageBox.Show("please fill all fields");

And recursion search:

public IEnumerable<T> ScanForControls<T>(Control parent) where T : Control
{
    if (parent is T)
        yield return (T)parent;

    foreach (Control child in parent.Controls)
    {
        foreach (var child2 in ScanForControls<T>(child))
            yield return (T)child2;
    }
}

Is there a way to fix the code to check if a textbox or combobox is empty?

Presumably you want to do something with the data after CheckEmpty() so that calling code needs to know the result of the test to decide if it should continue - CheckEmpty() should probably be a function.

Sub Test()

    If (Not CheckEmpty()) Then
        '// come controls were empty
        Exit Sub
    End If

    MsgBox "do work"
End Sub

Function CheckEmpty() As Boolean

    Dim ctrl As Control
    Dim gotError As Boolean

    '// loop controls, all empty ones are red otherwise they are reset to white
    For Each ctrl In Me.Controls
        If TypeOf ctrl Is MSForms.ComboBox Or TypeOf ctrl Is MSForms.TextBox Then
            If ctrl.Value = Empty Then
                gotError = True
                ctrl.BackColor = RGB(255, 0, 0)
            Else
                ctrl.BackColor = vbWindowBackground
            End If
        End If
    Next ctrl

    If (gotError) Then MsgBox "Please complete all missing information"

    CheckEmpty = Not gotError
End Function

Warning message in Excel macro if combobox null

You're not checking the Text property of your ComboBox. You should process like this.

Private Sub CommandButton1_Click()
    If (ComboBox1.Text = "") Then
        MsgBox "ComboBox Has No Data"
        Exit Sub
    End If

    Workbooks("Select Project.xlsm").Sheets("Sheet1").Range("B2").Value =  ComboBox1.Value
    Workbooks("Select Project.xlsm").Sheets("Sheet1").Range("C2").Value = ComboBox2.Value

End Sub

---

What changed ?

I changed If IsNull(ComboBox1) Then with If (ComboBox1.Text = "") Then so this will check the Text property in your ComboBox.

I also added Exit Sub to leave the function if the ComboBox is empty so it doesn't commit the operation after.

Combobox null in if statement

Nothing is ever equal to Null, not even another Null.

Use IsNull() to check whether the combo box is Null.

'If ProjectAddAllDueDateAutoCmBx = Null Then
If IsNull(ProjectAddAllDueDateAutoCmBx) = True Then

How to check if a selected item from an editable Combobox is empty

A better way:

comboBox.getSelectedIndex()

it will return -1 if the value is empty or null or not valid(matched) value.

Find the sample code here Editable ComboBox

---

--EDIT--

Delete button is clicked

if (jDatabaseComboBox.getSelectedIndex() == -1) {
    System.out.println("Please select a database name.");
} else {
    System.out.println("database name is deleted successfully.");
}

---

Related Topics