php与mysql的级连菜单，体现方法一（自家用）

不做什么解释了，早写的了，已经忘的差不多了，使用只要更改相应的sql语句就可以

//js的脚本完成张合

$GLOBALS["ID"] =1;

$layer=1;

$con=mysql_connect("127.0.0.1","root","");

if(!$con)

{

echo "级连菜单库连接出错！";

exit();

}

mysql_select_db("soohuo");

$sql="select * from t_class where parent_id=0";

$result=mysql_query($sql,$con);

$num=mysql_num_rows($result);//计算是否有上级

if($num0)

{

show_child($con,$result,$layer,$ID);

}

function show($con,$pid)

{

$var_td="";

$var_tr="";

$sql="select * from t_class where parent_id=$pid";

$result1=mysql_query($sql,$con);

$j=0;

while($row=mysql_fetch_array($result1))

{

$sql="select * from t_class where parent_id=".$row["class_id"];

$result2=mysql_query($sql,$con);

$num2=mysql_num_rows($result2);

//$var_td="";

if($num2==0)

{

$var_td.="

".$row["class_name"]."

";

$j++;

if($j%5==0)//每行的显示数

$var_td.="";

}

else

{

$var_tr=$var_tr."

".$row["class_name"]."

".show($con,$row["class_id"])."

";

//show_child($con,$result2,$layer);

}

}

$var="".$var_td."".$var_tr."";

return $var;

}

function show_child($con,$result,$layer)

{

$numrows=mysql_num_rows($result); //计算有多少个一级项

if($numrows0)

{

echo "";

while($row=mysql_fetch_array($result))

{

$pid=$row["class_id"];

$sql="select * from t_class where parent_id=$pid";

$result_sub=mysql_query($sql,$con);

$num_2=mysql_num_rows($result_sub);

if($num_20)

{

echo "

".$row["class_name"]."

";

echo "";

echo "

";

echo show($con,$pid);

echo "

";

}

else

{

}

}

echo "";

}

}

mysql_close($con);

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