验证PHP中的浮点数

Question

How can I validate to enter only float numbers from 1.0 -5.0 ? My system right now can accept:

• negative float
• negative integers
• symbols like + , it is not displayed in the database
• letters like a , it is not displayed in the database.

Below I have some code for checking to enter float number.

savelibscores.php

if(isset($_POST['submit'])){

$value1=$_POST['s3'];
$value2=$_POST['s4'];
$value3=$_POST['year'];


if((filter_var($value1,FILTER_VALIDATE_FLOAT)&& $value1>0) && (filter_var($value2,FILTER_VALIDATE_FLOAT) && $value2>0)) {
echo 'TRUE.';

} else {
    echo 'FALSE.';
}

if(!empty($value1) && !empty($value2) && !empty($value3)){
    $sql=mysql_query("INSERT INTO `library`(s3,s4,year) VALUES ('".$value1."','".$value2."','".$value3."')")or die(mysql_error());
}
else{
    echo "Please fill all the fields. Please be sure to use float values also.";
}

}

Answer 1

I pulled this from PHP's website http://php.net/manual/en/filter.examples.validation.php and http://php.net/manual/en/filter.filters.validate.php

if(isset($_POST['submit'])){

  $value1=$_POST['s3'];
  $value2=$_POST['s4'];
  $value3=$_POST['year'];
  $options = array(
    'options' => array(
                      'min_range' => -5,
                      'max_range' => 1,
                      )
   if(!empty($value1) && !empty($value2) && !empty($value3)){

    if((filter_var($value1,FILTER_VALIDATE_FLOAT,$options) && (filter_var($value2,FILTER_VALIDATE_FLOAT,$options))) 
      {
        echo 'TRUE.';
        $sql=mysql_query("INSERT INTO `library`(s3,s4,year) VALUES ('".$value1."','".$value2."','".$value3."')")or die(mysql_error());
      } else {
        echo 'Please be sure to use float values.';
      } 

} else {
    echo "Please fill all the fields. Please be sure to use float values also.";
}
}