![](/img/trans.png)
[英]How to check if the user has entered or not entered data to Mysql using PHP?
[英]PHP & MySQL check database if data is entered question
我想知道如何檢查特定帖子的數據庫中是否no tags have been entered
,如果沒有,則顯示no tags have been entered
。 如何使用PHP執行此操作?
這是我的PHP和MySQL代碼。
$tag = array();
$dbc = mysqli_query($mysqli, "SELECT tags.tag
FROM posts_tags
INNER JOIN tags ON tags.id = posts_tags.tag_id
WHERE posts_tags.post_id = '" . $post_id . "'
GROUP BY tags.tag");
if (!$dbc) {
print mysqli_error($mysqli);
} else {
while($row = mysqli_fetch_array($dbc)){
$tag[] = $row['tag'];
}
}
如果標簽數組為空,則沒有標簽:
if(empty($tag)){
echo 'no tags have been entered';
}
您還可以檢查返回的行數:
if(mysqli_num_rows($dbc) == 0){
echo 'no tags have been entered.';
}
使用mysqli_num_rows
和類似的代碼:
$tag = array();
$dbc = mysqli_query($mysqli, "SELECT tags.tag
FROM posts_tags
INNER JOIN tags ON tags.id = posts_tags.tag_id
WHERE posts_tags.post_id = '" . $post_id . "'
GROUP BY tags.tag");
if (!$dbc)
{
print mysqli_error($mysqli);
}
elseif(!mysqli_num_rows($dbc))
{
echo "no tags have been entered";
}
else
{
while($row = mysqli_fetch_array($dbc))
{
$tag[] = $row['tag'];
}
print_r($tag);
}
$(“。signup_name_image”)。hide();
var error_signup_name = false;
$(".signup_name").blur(function(){
check_signup_name();
});
function check_signup_name() {
var signup_name = $.trim($('.signup_name').val());
if (signup_name == '' || signup_name.length < 6 || signup_name.length > 50 ) {
$(".signup_name").css({"border":"1px solid #ff0000"});
$(".signup_name_image").show();
$(".signup_name_show").html("• Write Full Name in 6 to 50 alphabets");
**$(".signup_name").focus();**
error_signup_name = true;
} else if (/^[a-zA-Z0-9- ]*$/.test(signup_name) == false){
$(".signup_name").css({"border":"1px solid #ff0000"});
$(".signup_name_image").show();
$(".signup_name_show").html("• Contain invalid character");
**$(".signup_name").focus();**
error_signup_name = true;
}else {
$(".signup_name").css({"border":"1px solid #21cc00"});
$(".signup_name_image").hide();
}
}
$("#signup_form").submit(function(){
error_signup_name = false;
check_signup_name();
if (error_signup_name == false) {
return true;
} else {
return false;
}
});
$(".signup_name_image").hover(function(){
$(".signup_name_show").show();
}, function() {
$(".signup_name_show").hide();}
);
現在焦點停留在同一字段上如何在提交時關注字段
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.