Is it valid to define function(json) and if yes what does it mean? [closed]

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    $.getJSON(link,function(json)
       {
            if( json.length> 0)
       {

document.form_reserve.action ="http://localhost/ReserveRoomsBackend.php?        

bldg_number="+json[0].bldg_number +" & room_number="+json[0].room_number;
        document.getElementById("form_reserve").style.display = "block";
    }
             else
       {
      开发者_如何学Go     document.getElementById("label").style.display = "block";
       }

alert("inside json finction" + json.length+"  "+json[0].room_number+"   "+json

[0].bldg_number);
        }); //.getJSON

    }//doAjaxPost

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it's just an argument. The function expects ONE argument which is a JS object that jQuery has evaluated from a JSON string.

You're potentially confused by the fact that the { is on the next line, but it's the same as:

function(whatever){

---

You are calling the function $.getJSON (part of jQuery I guess) with an anonymous function as second parameter/argument (as a callback in this situation). Those anonymous functions are like "normal" functions, they just don't have a name and since you pass this function to getJSON as a reference, jQuery is able to call your function. So, yes it's valid. If this is what you meant.

---

In this context, json is a parameter passed to a function object, so yeah it's fine (although it's not very representative of the objects content) - it could be named anything.

In this case it could be called "rooms", and you would could call rooms[0].room_number instead of json[0].room_number.

For example, in this case "message" is the name of the parameter:

showAlertDialog("This an example");

function showAlertDialog(message) {
    alert("Your message was:" + message);
}

"json" is often used as the name for the response object in jQuery examples (as it is in your case here).