CODEIGNITER-消息：试图获取非对象的属性

Question

I got the following message:

A PHP Error was encountered

Severity: Notice

Message: Trying to get property of non-object

Filename: models/usermodel.php

Line Number: 4146

and here is my function where the line 4146 is:

else if($resultRes->average<'3' &&  $resultRes->average>='2')

This is the full function code. I have the same message for line 4137, 4140, 4143, 4146 and 4149

function get_Ranking($resid=''){
$sql="select ((Qrating+Srating+Drating+Crating)/4) as average from testimonial where RestId=".$resid;
$query=$this->db->query($sql);
$resultRes=$query->row();
if($resultRes->average == '5'){
return '050';
}
else if($resultRes->average<'5' &&  $resultRes->average>='4'){
return '040';
}
else if($resultRes->average<'4' &&  $resultRes->average>='3'){
return '030';
}
else if($resultRes->average<'3' &&  $resultRes->average>='2'){
return '020';
}
else if($resultRes->average<'2' &&  $resultRes->average>='1'){
return '010';
}

else{
return '000';
}
}

How can i fix it?

Answer 1

It's because some of your queries are empty.

if($query->num_rows() != 0)

first

Answer 2

Try with

if($resultRes[0]['average'] == '5'){
    return '050';
}
else if($resultRes[0]['average'] < '5' &&  $resultRes[0]['average'] >= '4'){
    return '040';
}

Since it will return an single row only,You can either use $resultRes['average'] directly.

Answer 3

Try to print the $resultRes before getting average from it.

$resultRes=$query->row();
printr($resultRes);

also print the last query and check whether your parameters are correctly populated in the query using below query.

echo $this->db->last_query();

It can be the case your parameter is empty and no record retrieved from table.