Valid C# Syntax

Question

Is this valid C# syntax?

tboxUserName.Text = "This is silly";

if (tboxUserName.Text == NULL)
{
tboxUserName.Text = tboxUserName.Text + "Very Very silly!";
}

Can you add to the contents of a field in the above way?

Roy S · Answer

yes, that's the right way to append something to a string. But you'll probably get an syntax error on the 'NULL', it should be in lowercase 'null'.

richard smith · Answer

That is my desired outcome, but for some reason it is not! Anywho, thank you for confirming that is valid C# syntax.

Vulpes · Answer

I would have expected the textbox to show: This is sillyVery Very silly!

richard smith · Answer

Maybe that was a bad example then. I am trying to combine two values, and my 1st value is getting overwritten. So for example sake... tboxUserName.Text = "This is silly"; tboxUserName.Text = tboxUserName.Text + "Very Very silly!"; My first value is getting overwritten by my 2nd value?

Vulpes · Answer

It is valid C# syntax but very silly for three reasons: 1. You wouldn't test a string for nullness immediately after setting it to a string literal! 2. The Text property of controls is never 'naturally' null in any case - it's default value is an empty string. 3. If you concatenate a null string with a non-null string, the former is treated as if it were empty and so, if you know it's null, concatenation is a pointless operation. However, there's nothing wrong with setting the Text property of a control to its existing value concatenated with one or more non-null strings. This is quite a common operation.

richard smith · Answer

That was just a typing error on my case. Argh! I was afraid that was valid syntax and I messed up somewhere else and that is why the data isn't displaying properly!