C# validating combo box with text.

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1.80/5 (3 votes)

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Afternoon,

I have a problem with my combo box validation, I need it so if you select Edinburgh twice in another combo box it displays an error message. This is my code so far. I am hoping someone can help, sorry if it isn't very detailed.

What I have tried:

<pre>f (CmbDepa.Text == "Edinburgh" && CmbArrival.Text == "Edinburgh")
            {
               MessageBox.Show("You cant select edinburgh twice");
            }
            else
            {
                Listbox1.Items.Add(CmbDepa.Text);
            }

}

Posted 18-Dec-18 5:09am

Member 14093842

Updated 18-Dec-18 5:59am

v3

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[no name] 18-Dec-18 11:15am

SelectedIndex property should give you index number which is integer. If you need to check for text you can do with CmbDepa.SelectedItem.ToString()

Member 14093842 18-Dec-18 11:19am

How would I edit my code for this to work? Sorry i'm new to C# and coding

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F-ES Sitecore · Answer 1 · 2018-12-18T05:28:00

Solution 1

You assign using "=" and compare using "==" so change to "==".

if (CmbDepa.SelectedIndex == "Edinburgh") && (CmbArrival.SelectedIndex == "Edinburgh")

Next you shouldn't use exceptions for things that are expected. Exceptions are for...exceptions :) Forget all the trys etc, just show a message

if (CmbDepa.SelectedIndex == "Edinburgh") && (CmbArrival.SelectedIndex == "Edinburgh")
{
    MessageBox.Show("You cant select edinburgh twice");
}
else
{
    Listbox1.Items.Add(CmbDepa.Text);
}

Posted 18-Dec-18 5:28am

F-ES Sitecore

Comments

Member 14093842 18-Dec-18 11:34am

Hello thanks for your help! When I have entered the code into my program it is saying
Error CS0019 Operator '==' cannot be applied to operands of type 'int' and 'string' and Error CS1525 Invalid expression term '&&'

F-ES Sitecore 18-Dec-18 11:38am

If you want to compare the text you'll need .Text or .SelectedText, whatever the property is called (don't have the docs to hand), rather than .SelectedIndex

Member 14093842 18-Dec-18 11:57am

I have changed it to the correct way, but the validation isn't displaying a validation message when I run the code. I've updated the code.