The result of non-null str==0 is True

Here bool actually is true .....
This is why

Reply to discussion (solution)

You so

Or

Look at the results, and then analyze it yourself.

You so

Or

Look at the results, and then analyze it yourself.
But does the OP 0 in PHP represent an empty string?

Like upstairs

That's how I analyze it.

echo $str > 0 results null
echo $STR < 0 results NULL
echo $str = = 0 Result 1

Because $str is a string, itself is not a number, so as a number $str is indeed false,php false==0 is true

Refer to this post for me. When I search for a database, the varchar field uses col=0 to search for the result incorrectly swapped with Col is null after correct
It should be the same.
http://bbs.csdn.net/topics/390529217

Upstairs explanation makes sense.

It's a string I thought I'd convert 0 to a string first!!!!!

= = Do compare when type conversion string and numeric comparison if the string is not 0 all converted to 0 to do the comparison result is certainly true you can try ' = = = ' To do the comparison will understand

It's a string I thought I'd convert 0 to a string first!!!!!

Oh, let you use those to do the experiment you can not see, there is no way

You so

Or

Look at the results, and then analyze it yourself.
But does the OP 0 in PHP represent an empty string?
Hey

