how to pass data from textbox in form1 to combobox in form2

[C# Programming]

namespace Passing_Data
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{
Form2 frm = new Form2(textBox1.Text);
frm.Show();

}

private void Form1_Load(object sender, EventArgs e)
{

}
}
}
FORM 2:
namespace Passing_Data
{
public partial class Form2 : Form
{
public Form2(String strTextBox)
{
InitializeComponent();
label1.Text = strTextBox;
}

private void Form2_Load(object sender, EventArgs e)
{

}

private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{

}
}
}

this code allows me to enter data in textbox on first form and hit button and see it displayed on second form in label.
is there a way to enter data in textbos on first form and hit button and see data entered into combobox on second form?
thank you