int CId = 0; private void button1_Click(object sender, EventArgs e) { try { if (textBox1.Text == "" || textBox2.Text == "" || comboBox1.SelectedIndex == -1 || textBox3.Text == "")what error is found is this code

Question

I have an error of (object reference not set to an instance of an object).

Answer 1

Hi,

The error message means one of the objects you are using is null. You need to make sure the objects are instantiated before you use them.

Best Regards,

Ian Xue

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