CI 获取数据库数据类型总是为STRING 的解决方案

This isn’t something I have time to do today, but for anyone else who comes across this problem, you can probably enable json_encodeto output numbers from active records with the following steps:

1) Modify the mysql/mysql_resultphp file to include the$field->numeric metadata attribute.
2) Add an extra step to active record queries that uses CodeIgniter’s $this->db->field_data() totest for any fields with numeric==1
3) If numeric==1, cast that field’s value to a number.

function field_data()
    {
        $retval = array();
        while ($field = mysql_fetch_field($this->result_id))
        {    
            $F                = new stdClass();
            $F->name         = $field->name;
            $F->type         = $field->type;
            $F->default        = $field->def;
            $F->max_length    = $field->max_length;
            $F->primary_key = $field->primary_key;
                        $F->numeric = $field->numeric; // <!-- ADD THIS LINE
            
            $retval[] = $F;
        }
        
        return $retval;
    } 

Heavy reliance on JSON in my scenario might make the extra effortworthwhile, but most people might never run into this.

2、It’s a blunt wayto solve the problem, but “good enough” for me. The functioncomments are based on PHP’s settype() documentationat http://us2.php.net/manual/en/function.settype.php

<?php

function cast_fieldtypes($record, $fieldTypes) {
    foreach($record as $fieldName => $value) {
        if(isset($fieldTypes[$fieldName])) {
            $type = $fieldTypes[$fieldName];
            $value = $record[$fieldName];
            switch ($type) {
                case 'boolean':
                case 'bool':
                    $value = (bool) $value;
                    break;
                
                case 'integer':
                case 'int':
                    $value = (int) $value;
                    break;

                case 'float':
                    $value = (float) $value;
                    break;
                    
                case 'string':
                    $value = (string) $value;
                    break;

                default:
                    break;
            }
            $record[$fieldName] = $value;
        }
    }
    return $record;
}
?> 

Here’s an exampleof how to use it:

// Declare the types for some of the fields (not necessarily all of them)
$fieldTypes = array(
    'weight'=>'int',
    'revision'=>'int',
    'is_visible'=>'bool',
);
$record = $this->db->get_where('content', array('id'=>1));
$casted_record = cast_fieldtypes($record, $fieldTypes);
echo json_encode($casted_record);