带mysql表的If-else语句PHP
我需要做一个if-else声明,如果用户是出价最高的人,它将阻止用户对某个项目进行竞价。我想会有点像这样带mysql表的If-else语句PHP,php,mysql,if-statement,Php,Mysql,If Statement,我需要做一个if-else声明,如果用户是出价最高的人,它将阻止用户对某个项目进行竞价。我想会有点像这样 if ($accountid = the accountid in the bidhistory table) { echo "You are the highest bidder!"; } else { $sql="INSERT INTO bidhistory (accountid, biditemid) VALUES ($accountid, $itemid)"; mysq
if ($accountid = the accountid in the bidhistory table)
{
echo "You are the highest bidder!";
}
else
{
$sql="INSERT INTO bidhistory (accountid, biditemid)
VALUES ($accountid, $itemid)";
mysql_query("
UPDATE bidhistory
SET bidprice = bidprice + 1
WHERE biditemid = " .
@mysql_escape_string($itemid));
$result=mysql_query($sql) or die("Error in adding bid for item: ".mysql_error());
}
?>
我不确定如何从bidhistory表中引用accountid。另外,如果有更好的方法,请告诉我赖特的方向。谢谢 注:
- 您可以先获取特定项目的最高出价行。
然后检查最高出价者(
)是否与当前用户相同accountid
- 您可以查看我在
/*中引用的一些行的注释*/代码>
$result = mysql_query("SELECT accountid FROM bidhistory WHERE biditem = '$itemid' ORDER BY bidhistoryid DESC LIMIT 1"); /* GET THE LAST ROW FOR WHO BIDS LAST; AND REPLACE NECESSARY COLUMN NAME (unique/primary) - bidhistoryid */
while($row = mysql_fetch_array($result)){
$checkaccountid = $row['accountid']; /* STORE THE USER THAT BIDS LAST FOR THIS ITEM */
}
if($checkaccountid == $accountid){ /* THEN COMPARE IT WITH THE CURRENT USER */
/* CODE YOU WANT TO DO IF HE/SHE IS THE LAST BIDDER ALREADY */
}
else {
/* IF NOT, HE/SHE CAN STILL BID */
}
但是我建议您使用mysqli\u*
而不是mysql\u*
API
$con = new mysqli("YourHost", "Username", "Password", "Database"); /* REPLACE NECESSARY DATA */
/* CHECK CONNECTION */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
if($stmt = $con->prepare("SELECT accountid FROM bidhistory WHERE biditem = ? ORDER BY bidhistoryid DESC LIMIT 1")){
$stmt->bind_param("i",$itemid); /* BIND THIS VARIABLE TO YOUR QUERY ABOVE */
$stmt->execute(); /* EXECUTE THE QUERY */
$stmt->bind_result($checkaccountid); /* STORE THE RESULT TO THIS VARIABLE */
$stmt->fetch(); /* FETCH THE RESULT */
if($checkaccountid == $accountid){
/* CODE YOU WANT TO DO IF HE/SHE IS THE LAST BIDDER ALREADY */
}
else {
/* IF NOT, HE/SHE CAN STILL BID */
}
$stmt->close();
} /* END OF PREPARED STATEMENT */
在
bidhistory
表中,它是否有主键?像bidhistory\u id
?所以它将是唯一的。@LoganWayne是的,它是唯一的。我一直收到一个错误,说$checkaccountid未定义。@LuluSparks-您是否用相应的列名(bidhistoryid
)更改了查询?或者尝试在服务器端运行此查询从bidhistory中选择accountid,其中biditem=1 ORDER BY bidhistoryid DESC
或使用任何有效的biditem
编号。你用了什么?我的第一套代码,还是第二套?我用了第一套。你说我更改了查询是什么意思?@LuluSparks-我指的是bidhistoryid
。您的bidhistory
表的唯一/主键id是什么?@LuluSparks-尝试在服务器端(在您的PhpMyAdmin页面中)运行此查询从bidhistory中选择accountid,其中biditem=1 ORDER BY bidhistoryid DESC
。让我们看看是否有结果。