PHP在文本框中提交名称

I have just started learning php. However I am having trouble with the code below. I know it automatically prints out You're not a member... But when I then enter "letmein" it still says I am not a member. Any guidance would be much appreciated

    <html>
    <head>
    <title>A BASIC HTML FORM</title>

    <?PHP

    $username = $_POST['username'];

    if ($username == "letmein") {

    print ("Welcome back, friend!");

    }
    else {

    print ("You're not a member of this site,goodbye");

    }

    ?>


    </head>
    <body>
    <FORM NAME ="form1" METHOD ="POST " ACTION = "basicForm.php">


    <INPUT TYPE = "TEXT" VALUE ="username" Name="username">
    <INPUT TYPE = "Submit" Name = "Submit1" VALUE = "Login">

    </FORM>
    </body>
    </html>

You have an extra space in the METHOD ="POST " of your form.

Change it to METHOD="POST".