Php performs webpage login pages and transmits data. if the variable is invalid, the problem is solved.

Php performs webpage login pages and transmits data. if the variables are invalid, the PHP login interface is solved.

Php sets a total of three variables, and found that only $ select is valid at the time of determination, and the other two are invalid. what is the problem?
Please answer your questions and hurry up with the task.
I am very grateful for your help.
Logon interface code:



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Southwest China University for Nationalities Lab teaching management system   User logon

 

 

Php detection code:

@ $ Textfield =$ _ POST ['textfield'];
@ $ Textfield2 = $ _ POST ['textfield2'];
@ $ Select = $ _ POST ['select'];
If ($ textfield = "a") & ($ textfield2 = "123") & ($ select = "B") // enter, 123. invalid instructor selection. remove any
Echo"

Fffffff

"; // Condition. if any data is input, it is found that ($ select =" B ") is valid,
Else // The other two statements are useless and must be false.
Header ("Location: http: // localhost/phpmyadmin/Documentation.html ");
Exit;
?>

Reply to discussion (solution)

How many forms do you want to write !!!

How many forms do you want to write !!!
Do not understand?

A form is OK. keep the first form and delete all the other forms.

That's it.

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Southwest China University for Nationalities
 
       
 
      
 
     
 
     
 
      
 
       
 
        
Lab teaching management system
 
       
 
      
 
     
 
     
 
      
 
       
 
        
 
 
        
User logon
 
       
 
       
 
        
 
 
       
 
      
 
     
 
 
   
 
  
 
 
 
 

You have to go against the sky. in a text box and a form, you can directly put the form on the outer layer of the table. you only need one form.