Valid C# Syntax

richard smith

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?

6 Replies

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Roy S13y ago
Accepted 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 smith13y ago
That is my desired outcome, but for some reason it is not!

Anywho, thank you for confirming that is valid C# syntax.
Vulpes13y ago
I would have expected the textbox to show:

This is sillyVery Very silly!
richard smith13y ago
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?
Vulpes13y ago
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 smith13y ago
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!