To query the contents of a database, build an HTML file, and then build a from form, as in the example below.
<formAction= "./loginchuli.php"Method= "POST"> <Div>User name:<inputtype= "text"name= "UID" /></Div> <Div>Password:<inputtype= "Password"name= "pwd" /></Div> <Div><inputtype= "Submit"Disabled= "Disabled"value= "Login"onclick= "return check ()" /></Div></form>
Then write the php file to connect to the database
$uid = $_post["UID"]; $pwd = $_post["pwd"]; $db = new mysqli ("localhost", "root", "123", "mydb"); if (mysqli_connect_ Error ()) {die ("Connection failed! ");} $sql = "Select pwd from users where uid= ' {$uid} '"; $reslut = $db->query ($sql); $arr = $reslut->fetch_row (); if ($arr [0] = = $pwd &&!empty ($pwd)) {echo "<Script>window.location.href='main.php'</Script>";} else{header ("location:login.php");}
Pay attention to the rigor of your account password here.
Data access (Login database query content on Web page display)