Getting Data from a Post form Request

Hello everyone,

I am currently using the Arduino Uno Wifi Rev 2 and I’ve built a web server that displays a page to any client that is on the Arduino’s network.

My problem is that i have a sensor that has a default value of 25.

What i want to achieve is submit a GET or a POST request on the arduino and change that value to what ever the value is on the input.

Below is the form i am using:

I been searching for 2 hours with no luck on an example that can help me.

client.println("<form action=\"/\" method=\"GET\"");
client.println("<h3>Temp");
client.println("<output name=\"tempOutputName\" id=\"tempOutputId\">24</output>");
client.println("</h3>");
client.println("<input type=\"range\" min=\"20\" max=\"35\" name=\"tempInputName\" id=\"tempInputId\" value=\"24\" style=\"width:100%\" oninput=\"tempOutputId.value = tempInputId.value\">");

client.println("<button class=\"button\" type=\"submit\">Submit</button>");
client.println("</form>");

client.println("</div>");
client.println("<input type=\"range\" min=\"20\" max=\"35\" name=\"tempInputName\" id=\"tempInputId\" value=\"24\" style=\"width:100%\" oninput=\"tempOutputId.value = tempInputId.value\">");

What kind of value should the oninput property have?

PaulS:
What kind of value should the oninput property have?

The oninput just shows the value of the input while you drug the range of the input from min to max, basically it doesnt have anything to do with the data that i get after the Post or the Get request.

If i submit the form with a get request on the headers i get

Get /?tempInputName='here is the value of the input field'

The issue is that no matter what i try i get 0 with indexOf. All i want is to get the input value witch will be after = if its a GET