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Home Backend Development PHP Tutorial 关于foreach输出问题

关于foreach输出问题

Jun 23, 2016 pm 02:19 PM

$sql1="select * from y_cate order by asc";
$result1=mysql_fetch_array(mysql_query($sql1));
var_dump($result1);
foreach($result1 as $ke=>$a){
    echo $a."
";
}
?>
我想用foreach 来循环输出cate表的所有数据,为什么只输出一条数据的?求解答


回复讨论(解决方案)

$sql1="select * from y_cate order by asc";$result1 = mysql_query($sql1);while($row = mysql_fetch_array($result1)) {  foreach($row as $ke=>$a){    echo $a."<br>";  }}
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$sql1="select * from y_cate order by asc";
$result1=mysql_fetch_array(mysql_query($sql1));
var_dump($result1);
foreach($result1 as $ke=>$a){
echo $a."
";
}
?>
我想用foreach 来循环输出cate表的所有数据,为什么只输出一条数据的?求解答 1. 你的sql语句不会报错?order by asc,没有排序字段;
2. 没有执行 sql语句。mysql_query($sql1).


$sql1="select * from y_cate order by asc";
$result1=mysql_fetch_array(mysql_query($sql1));
var_dump($result1);
foreach($result1 as $ke=>$a){
echo $a."
";
}
?>
我想用foreach 来循环输出cate表的所有数据,为什么只输出一条数据的?求解答 1. 你的sql语句不会报错?order by asc,没有排序字段;
2. 没有执行 sql语句。mysql_query($sql1). 手误手误 ?

select * from y_cate order by asc的问题

order by没有指定字段,会报错:#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near "..........

$sql1="select * from y_cate order by asc";$result1 = mysql_query($sql1);while($row = mysql_fetch_array($result1)) {  foreach($row as $ke=>$a){    echo $a."<br>";  }}
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必须要用while么?
如果用while的话
[code] $sql1="select * from y_cate order by px asc";
$us=mysql_query($sql1);
while($result1=mysql_fetch_array($us)){
echo $result1['name'];

}[/code]
这样子不是更简洁??而且好像你那个方法输出的时候会重复输出,下面是输出的数据,重复了一次
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select * from y_cate order by asc的问题

order by没有指定字段,会报错:#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near "..........
亲,手敲的代码,手误漏掉了。请问我问的问题怎么解决


$sql1="select * from y_cate order by asc";$result1 = mysql_query($sql1);while($row = mysql_fetch_array($result1)) {  foreach($row as $ke=>$a){    echo $a."<br>";  }}
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Copy after login

必须要用while么?
如果用while的话
[code]  $sql1="select * from y_cate order by px asc";
                                $us=mysql_query($sql1);
                                while($result1=mysql_fetch_array($us)){
                                echo $result1['name'];

                                }[/code]
这样子不是更简洁??而且好像你那个方法输出的时候会重复输出,下面是输出的数据,重复了一次
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50b5b9555f97e.png
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0
0
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0

重复是因为你用了  mysql_fetch_array  换成 mysql_fetch_assoc后就不重复了,具体原因请百度下这两个函数,一看就明白.

版大给出的方法是正确的,你要输出每一条记录的每一项,这就是两个循环,while取每一条,foreach取每一项. 你改完的就循环了一次  当然不能实现你的需求啦

while($row = mysql_fetch_array($result1,MYSQL_ASSOC)) {
  foreach($row as $ke=>$a){
    echo $a."
";
  }
}

或者就用mysql_fetch_assoc/mysql_fetch_row

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