Using the '??' operator in PHP7
How to use the "??
" operator in PHP7? The following article will introduce to you the usage of "??" in PHP7. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to everyone.
??
operator in PHP7, let’s take a look at its specific function
??
is equivalent to
1 |
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Determine whether a variable a exists. If it exists, assign variable a. If it does not exist, assign variable b
Note that it is to determine whether a variable exists, not to determine whether a variable is empty
Look at the code directly
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