CS1525 C# Invalid expression term 'string' : <p>I have this error and I have no ideo about what should I do</p>

<p>The aim is when I click to button, it should read the word in textbox and save it into the string variable by its new factor.I have the error oin the topic</p>

<pre><code> private void panel_button_kelimeekle_kaydet_Click(object sender, EventArgs e)
        {
            if(panel_checkbox_ing.Checked)
            {
                string (panel_textbox_kelimeekle_yab.Text) = Ingkelimeler[(Ingkelimeler.Length+1)];

            }

}
</code></pre>
