TextChanged event for combobox C#

Question

Basically the in the code below i am trying to loop through the array and if the current text in the combobox does not match anything in the array it will throw an error. However i cannot get it to fire on the event TextChanged event.

Any help is greatly appreciated

string[] SRtier1 = { "Option1", "Option2", "Option3", "Option4", "Option5" };        

private void SRcmb_tier1_TextChanged(object sender, EventArgs e)
    {
        //Loop SRtier1 Array to ComboBox
        for (int i = 0; i < SRtier1.Length; i++)
        {
            if (SRcmb_tier1.Text != SRtier1[i])
            {
                MessageBox.Show("Please select one of the options provided.");
            }
        }
    }

Answer 1

如果您在TextChanged中有任何内容，请在事件中检查属性窗口

Answer 2

First, you have wrong loop implementation : in your code you're eager to fire the message SRtier1.Length times, what you want is, probably, to check the input and fire the message once:

private void SRcmb_tier1_TextChanged(object sender, EventArgs e)
{
    Boolean found = false;

    for (int i = 0; i < SRtier1.Length; i++)
    {
        if (SRcmb_tier1.Text == SRtier1[i])
        {
            found = true;
            break;
        }
    }

    if (!found)
       MessageBox.Show("Please select one of the options provided.");
}

Better solution is to use Linq :

   private void SRcmb_tier1_TextChanged(object sender, EventArgs e) {
     if (!SRtier1.Any(item => item == SRcmb_tier1.Text)) 
       MessageBox.Show("Please select one of the options provided.");
   }

And finally, check if SRcmb_tier1_TextChanged is assinged to TextChanged of SRcmb_tier1 as von v. said in comments.