访问PHP数组对象中的项

I have an array of the record retrieved from a SQL server database stored in an object $result. I will like to access each item in the array object and print it out to the screen. How can I achieve this? My attempt is below

我有一个从存储在对象$ result中的SQL服务器数据库中检索到的记录数组。我想访问数组对象中的每个项目并将其打印到屏幕上。我怎样才能做到这一点?我的尝试如下

$result = $DB->get_records_sql("SELECT  rawname, ID FROM mdl_tag where tagType = 'institution'"); 
$result = array();
        foreach ($result as $ $value) {
        echo $value;
        );
    }

1 个解决方案

#1

Here is the correct code:

这是正确的代码:

// Get results from table 'tag', where 'tagtype' matches 'institution', with no sorting and returning fields 'id' and 'rawname'.
$results = $DB->get_records('tag', ['tagtype' => 'institution'], '', 'id, rawname');
foreach ($results as $value) {
    echo $value->rawname;
}

So, there are a number of issues:

所以,有很多问题:

Use get_records, unless you really need to use get_records_sql.

使用get_records,除非你真的需要使用get_records_sql。

If you do need to use get_records_sql, then the table is called {tag} not mdl_tag, otherwise you'll run into problems on any server that uses a prefix other than 'mdl_' (e.g. when running phpunit or behat tests).

如果你确实需要使用get_records_sql,那么该表被称为{tag}而不是mdl_tag,否则你将在任何使用“mdl_”之外的前缀的服务器上遇到问题(例如,当运行phpunit或behat tests时)。

Writing $result = array(); immediately before looping through the result will throw away the details from the database and replace them with an empty array

写$ result = array();在循环结果之前,将立即丢弃数据库中的详细信息并将其替换为空数组

The results from get_records (or get_records_sql) are an array containing objects, each of which contains the values for the requested fields, so you need to access the individual value, not try to echo the entire object

get_records(或get_records_sql)的结果是一个包含对象的数组,每个对象都包含所请求字段的值,因此您需要访问单个值,而不是尝试回显整个对象

All database fields in Moodle are lowercase, so 'tagtype' not 'tagType', 'id' not 'ID'.

Moodle中的所有数据库字段都是小写的,因此'tagtype'不是'tagType','id'不是'ID'。

#1