6. Determine whether the file exists and output the content
$FileName="File.TXT";
if (File_Exists($FileName)){
Echo “
<![CDATA[”.File_Get_Contents($FileName).”]]>”;
}else
{
Echo”no”;
}
?>
7. Uninstall variable unset;
unset($var);
unset($var,$var1);
8.is_int;
Check whether the variable is an integer;
9.is_null;
Check whether the variable is NULL;
10.is_string
Check whether the variable is a string
11.is_real;
Alias for is_float()
12.isset
Check whether the variable is set
13.is_bool
Check whether the variable is of Boolean type
14.is_array
Check whether the variable is an array
15.is_object
Check whether the variable is an object
16.SubStr.
SUBSTR(String,Start,SelectNum)
echo substr(‘abcdef’, 1); // bcdef
echo substr(‘abcdef’, 1, 3); // bcd
echo substr(‘abcdef’, 0, 4); // abcd
echo substr(‘abcdef’, 0, 8); // abcdef
echo substr(‘abcdef’, -1, 1); // f
17.Nb2br
echo nl2br(“foo isn’tn bar”);
Convert escaped newlines into HTML
Original text: http://y312ff.blog.163.com/blog/static/12701109420119119575812/
lazycms::$sysname
This is the first time I see this expression. What does the double colon mean?
Answer:
Methods or properties directly belonging to the class.
That is, the use of static static methods or attributes.
Field operators are generally used to use the properties/methods of class A objects in class B objects!
class c
{
private static $_memory;
public static function autoload()
{
//Method body
}
}
c::$_memory;
c::autoload();
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