Php can determine whether a variable is an integer.

Method 1: You can use four homes or five to enter the number and compare it with the original number. for example, the result of floor (31) is 3. Obviously, 3 is displayed! 31, or use the ceil () function to determine whether

Method 1: You can use four homes or five to enter the number and compare it with the original number. for example, the result of floor (3.1) is 3. Obviously, 3! = 3.1, or use the ceil () function to determine whether it is an integer.

Method 2: Use the php built-in function is_int () to easily determine whether the number is an integer.

The code is as follows:

1. $ A = 3.3;
2. // Method 1
3. If (floor ($ a) ==$ ){
4. Echo "$ a is an integer! ";
5. } Else {
6. Echo "$ a is not an integer! ";
7. }
8. // Method 2
9. If (is_int ($ )){
10. Echo "$ a is an integer! ";
11. } Else {
12. Echo "$ a is not an integer! ";
13. }

Note:The is_int () and floor checks the type of the variable, instead of the content in the variable. when judging the string, you can use the following code instead:

1. Function str_is_int ($ str)
2. {
3. Return 0 === strcmp ($ str, (int) $ str );
4. }