Simple webserver (make button)

Hallo

I am trying to make a simple webserver to my automatic curtain.
i got the webserver running, but i dont know how to make a button there stay at the same page…

Now i got a href

client.println("<a href="/?1on" target=“inlineframe”>ON");

that work okey, but look stubit… So i want a button there do the same. I have try this

client.println("<input type=“button” value=“ON” onmousedown=“location.href (’/?on’);”/>");

When i click on the button i got redirectet to the page ( http://192.168.1.177/?on ), but when i click on the first href, i stay at the start page (http://192.168.1.177).
How do i get the botton to stay at the startpage and give me the “output” /?on like the href…

here is my code

#include <SPI.h>
#include <Ethernet.h>

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
byte ip[] = { 192, 168, 1, 177 }; // ip in lan
byte gateway[] = { 192, 168, 1, 1 }; // internet access via router
byte subnet[] = { 255, 255, 255, 0 }; //subnet mask
EthernetServer server(80); //server port

String readString; 

//////////////////////

void setup(){

  pinMode(4, OUTPUT); //pin selected to control
  //start Ethernet
  Ethernet.begin(mac, ip, gateway, subnet);
  server.begin();

  //enable serial data print 
  Serial.begin(9600); 
  Serial.println("servertest1"); // so I can keep track of what is loaded
}

void loop(){
  // Create a client connection
EthernetClient client = server.available();
  if (client) {
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();

        //read char by char HTTP request
        if (readString.length() < 100) {

          //store characters to string 
          readString += c; 
          //Serial.print(c);
        } 

        //if HTTP request has ended
        if (c == '\n') {

          ///////////////
          Serial.println(readString); //print to serial monitor for debuging 

          //now output HTML data header
             if(readString.indexOf('?') >=0) { //don't send new page
               client.println("HTTP/1.1 204 Zoomkat");
               client.println();
               client.println();  
             }
             else {
          client.println("HTTP/1.1 200 OK"); //send new page
          client.println("Content-Type: text/html");
          client.println();

          client.println("<HTML>");
          client.println("<HEAD>");
          client.println("<TITLE>Gardiner</TITLE>");
          client.println("</HEAD>");
          client.println("<BODY>");
          
          
client.println("<input type=\"button\" value=\"OFF\" onmousedown=\"location.href ('/?off');\"/>"); 


          client.println("<H1>Hennings Gardiner</H1>");

          client.println("<input type=\"button\" value=\"ON\" onmousedown=\"location.href ('/?on');\"/>"); 
          client.println("<a href=\"/?on\" target=\"inlineframe\">ON</a>"); 
//          client.println("<IFRAME name=inlineframe src=\"res://D:/WINDOWS/dnserror.htm\" width=1 height=1\">");
          client.println("<IFRAME name=inlineframe style=\"display:none\" >");          
          client.println("</IFRAME>");

          client.println("</BODY>");
          client.println("</HTML>");
             }

          delay(1);
          //stopping client
          client.stop();

          ///////////////////// control arduino pin
          if(readString.indexOf("1on") >0)//checks for on
          {
            digitalWrite(4, HIGH);    // set pin 4 high
            Serial.println("Led On");
          }
          if(readString.indexOf("1off") >0)//checks for off
          {
            digitalWrite(4, LOW);    // set pin 4 low
            Serial.println("Led Off");
          }
          if(readString.indexOf("2on") >0)//checks for on
          {
            digitalWrite(4, HIGH);    // set pin 4 high
            Serial.println("Led2 On");
          }
          if(readString.indexOf("2off") >0)//checks for on
          {
            digitalWrite(4, HIGH);    // set pin 4 high
            Serial.println("Led2 Off");
          }
          //clearing string for next read
          readString="";

        }
      }
    }
  }
}

No one..??

The below looks like a copy/paste error that might give unintended results. I don't understand your origional question.

          if(readString.indexOf("2off") >0)//checks for on
          {
            digitalWrite(4, HIGH);    // set pin 4 high
            Serial.println("Led2 Off");
          }

tf-uno:
How do i get the botton to stay at the startpage and give me the "output" /?on like the href..

When you use the hyperlink, you're loading the specified URL into 'inlineframe' (which I guess is an IFRAME).

The button seems to be loading the URL into the current window. If you want to be all AJAX-ey and load it into an IFRAME, leaving the current window on display, then you need to set that IFRAME's location to the URL rather than setting the current window's location.

None of this is Arduino-specific, so if you're having trouble figuring it out I suggest you start off with a hand-coded HTML page and get that doing what you want. There are plenty of HTML tutorials and guides that will explain how to get the effect you need. Once the HTML is right, just program your Arduino to serve out that HTML.