Value doesn't show up on a DataGridViewComboBox control

Question

After setting the values in the DataGridView, they don't show up on the control even though I can access them through the Value property.

The problem is that there is no default Value in the ComboBox cells.

void ComboBoxColumn()
{
    string[] values =  { "one", "two", "three" };
    string columnName = "Test";
    var column = new DataGridViewComboBoxColumn();
    column.Name = columnName;
    column.ValueType = typeof(string);

    foreach(string item in values)
    {
        column.Items.Add(item);
    }

    Grid.Columns.Add(column);

    // problematic part
    foreach(DataGridViewRow row in Grid.Rows)
    {
        row.Cells[columnName].Value = values[0];
    }
}

andre · Answer 1 · 2012-01-17T14:38:05.763

1

    void SetValues()
    {
        string[] values = { "one", "two", "three" };
        string columnName = "Test";
        var column = new DataGridViewComboBoxColumn();
        column.Name = columnName;
        column.ValueType = typeof(string);

        foreach (string item in values)
        {
            column.Items.Add(item);
        }

        dataGridView1.Columns.Add(column);
    }

On my machine this code is running. If I click the ComboBoxColumn I can see the tree values and choose one. What is your problem?

        foreach (DataGridViewRow row in dataGridView1.Rows)
        {
            row.Cells[columnName].Value = values[1];
        }

If you add this code, the default value of the combo box shows the value 'two'.

edited Jan 17 '12 at 14:38

answered Jan 17 '12 at 14:06

andre

140
1
10

That's not the problem, the problem is the second part. – mooper Jan 17 '12 at 14:07
row.Cells[columnName].Value = values[1]; also works. You didn't provide your code for RandomValue. – andre Jan 17 '12 at 14:20
Weird, doesn't work for me. Also, edited the question to make myself more clearer. – mooper Jan 17 '12 at 14:27
1

row.Cells[columnName].Value = values[1]; shows the value 'two' as default value. I don't understand your problem. – andre Jan 17 '12 at 14:28

justAuser · Answer 2 · 2012-01-17T14:29:10.300

1

    void AddComboColumn()
    {
        string[] values = { "one", "two", "three" };
        string columnName = "Test";
        var column = new DataGridViewComboBoxColumn();
        column.Name = columnName;
        column.ValueType = typeof(string);

        foreach (string item in values)
        {
            column.Items.Add(item);
        }

        dataGridView1.Columns.Add(column);

        foreach (DataGridViewRow row in dataGridView1.Rows)
        {
            row.Cells[columnName].Value = values[2];
        }
    }

These code work too... Check, may be problem in 'RandomValue(values);'? I haven't this part of code and can't tell for sure. P.S. In my prog default value == "three".

edited Jan 17 '12 at 14:29

answered Jan 17 '12 at 14:18

justAuser

60
1
11

I was talking about the default value in the combobox, not the dropdown menu. RandomValues() works fine. – mooper Jan 17 '12 at 14:24
If I understand You don't have dropdownlist? or You just don't have default value? – justAuser Jan 17 '12 at 14:33
I don't have the default values. – mooper Jan 17 '12 at 14:35
1

Funny, I can't repeat this problem. In my way all work great. – justAuser Jan 17 '12 at 14:43
Oh! good! I repeat! I have no default values only if I have column with same Name ("Test"). I call this method 2 times, and in second column I have no default values. Check, may be you have same Column names? – justAuser Jan 17 '12 at 14:47

score 0 · Answer 3 · edited Mar 18 '15 at 08:59

0

First Make name for combo box in datagridveiw ColDryg then in initvalue function write this code

  DataGridViewComboBoxColumn ColDryg =
 (DataGridViewComboBoxColumn)Gv_dtails.Columns["ColDryg"];
             ColDryg.DataSource = db.Drugs.ToList();
             ColDryg.ValueMember = "Id";
             ColDryg.DisplayMember ="Arabic_name";

you have table in database its name is Drug

edited Mar 18 '15 at 08:59

winner_joiner

12,173
4
36
61

answered Mar 18 '15 at 08:29

Mina Milad

1
1

score 0 · Answer 4 · answered Jan 17 '12 at 14:53

0

I cant reproduce your error. Here is my sample project

Try and give us anything else that might be the issue.

note: I copied your code directly (and then added in some rows)

answered Jan 17 '12 at 14:53

Jason Ridge

1,868
15
27

Value doesn't show up on a DataGridViewComboBox control

4 Answers4