Ask a question about ComboBox?

curlygoat

There is a drop-down form on the web page:
<select>
<option value="值">text</option>
</select>
What we can see is the text of the <option> item, select this item to get value="value".

The corresponding ComboBox control in C# Form is
What we see is the Items.Text property, but how is the value property assigned to each item?

苹果小刀

C# WinForm does not have this thing

yzx630

this.cmbSno.DataSource=ds.Tables["student"];
this.cmbSno.DisplayMember="Sno";
this.cmbSno.ValueMember="Sno";

andyleelee

Just use this directly comboBox1.SelectedItem

kalian2000

Specify DisplayMember and ValueMember when binding.

for example:

A table studentDetails, two fields (sno, sname), bound to Commbobox:

//Binding when FormLoad, display name
private void Form1_Load(object sender, EventArgs e)
        {
            SqlConnection con = new SqlConnection("server=.;database=student;uid=sa;pwd=0421");
            SqlDataAdapter sda = new SqlDataAdapter("select * from studentDetails", con);
            DataSet ds = new DataSet();
            sda.Fill(ds, "student");
            this.comboBox1.DataSource = ds.Tables["student"];
            this.comboBox1.DisplayMember = "sname";
            this.comboBox1.ValueMember = "sno";
        }
//Get the value of the currently selected item, that is, the student ID
private void comboBox1_SelectedValueChanged(object sender, EventArgs e)
        {
            this.textBox1.Text = this.comboBox1.SelectedValue.ToString();
        }