Question

我从Wordpress获得以下PHP错误：

Warning: Cannot modify header information - headers already sent by (output started at domain/public_html/sdapi/wp-content/plugins/testpost/testpost.php:74) in domain/public_html/sdapi/wp-admin/post.php on line 235

Warning: Cannot modify header information - headers already sent by (output started at domain/public_html/sdapi/wp-content/plugins/testpost/testpost.php:74) in domain/public_html/sdapi/wp-includes/pluggable.php on line 1196

使用此代码：

    <?php
/**
 * Plugin Name: testpost
 */
add_action( 'publish_post', 'testpost', 10, 1 );
function testpost( $post ) {

// ***** Get variables *****
$post_id = $post;
$post_object = get_post( $post_id );
$post_object->post_content;

$title = $post_object->post_title;
$source_url = get_permalink( $post_id );
$body = $post_object->post_content;

$titleprint = preg_replace("/\r?\n/", "\\n", addslashes($title));    
$bodyprint = preg_replace("/\r?\n/", "\\n", addslashes($body));
$posturlprint = preg_replace("/\r?\n/", "\\n", addslashes($source_url));




// ***** Run script *****
echo "<script>

var Request = new XMLHttpRequest();

Request.open('POST', '****POSTURL****');

Request.setRequestHeader('Content-Type', 'application/json');
Request.setRequestHeader('Accept', 'application/json');
Request.setRequestHeader('Authorization', '****TOKEN****');

Request.onreadystatechange = function () {
if (this.readyState === 4) {
}
};

var body = {
'article': {
'uuid': '090bda74-b021-4c7c-a44a-44f33bba32142',
'title': '". $titleprint ."',
'source_url': '". $posturlprint ."',
'body': '". $bodyprint ."'
}
};

Request.send(JSON.stringify(body));


</script>";




}
?>

*通过粘贴添加<?php之前的空格，无法摆脱它：（

起初我认为正是这里广泛解释的空白问题：How to fix "Headers already sent" error in PHP。

不幸的是，它不是（易于修复）而且我认为这是“打印，回声问题”，如同一个答案所述。

不幸的是我需要使用echo，否则我的插件根本不起作用。

是否有替代方法可以在这里使用echo，或者可能是某种方式？希望有人可以提供帮助。

Answer 1

似乎在代码的开头存在空格。这就是你得到这个警告的原因。在php标签的开头和结尾不应该有任何空格。

Answer 2

尝试使用ob_start();来阻止标头已发送问题。这个问题主要是由于PHP代码中有额外的空格，或者在关闭?>标记之前你有太多的空格，你也可以避免使用这个结束标记，请删除这些空格。

<?php
 ob_start();
/**
 * Plugin Name: testpost
 */
add_action( 'publish_post', 'testpost', 10, 1 );
function testpost( $post ) {

// ***** Get variables *****
$post_id = $post;
$post_object = get_post( $post_id );
$post_object->post_content;

$title = $post_object->post_title;
$source_url = get_permalink( $post_id );
$body = $post_object->post_content;

$titleprint = preg_replace("/\r?\n/", "\\n", addslashes($title));    
$bodyprint = preg_replace("/\r?\n/", "\\n", addslashes($body));
$posturlprint = preg_replace("/\r?\n/", "\\n", addslashes($source_url));

// ***** Run script *****
echo "<script>

var Request = new XMLHttpRequest();

Request.open('POST', '****POSTURL****');

Request.setRequestHeader('Content-Type', 'application/json');
Request.setRequestHeader('Accept', 'application/json');
Request.setRequestHeader('Authorization', '****TOKEN****');

Request.onreadystatechange = function () {
if (this.readyState === 4) {
}
};

var body = {
'article': {
'uuid': '090bda74-b021-4c7c-a44a-44f33bba32142',
'title': '". $titleprint ."',
'source_url': '". $posturlprint ."',
'body': '". $bodyprint ."'
}
};

Request.send(JSON.stringify(body));

</script>";
}
?>

发送头插件中的echo的替代方案

2 个答案: