Question

This is my Javascript code:

expr = "A simple string"
$.ajax({
    type: "GET",
    url: "/ajaxrequest/get_dt_paragraphs?expr=" + expr,
    timeout: 8000,
    success: function(data) { doSomething(); }
});

In my django view, I wrote this method:

def get_dt_paragraphs(request):
    if request.method == 'GET':
        my_string = request.GET["expr"]
        # print on the console for debugging purposes.
        print my_string
    # Do other stuff

The output on the console is [u”A simple string”], so I discovered that the parameter name returns an array. Of course, I could write request.GET[“expr”][0] to get the string, but I would like to know why I get a list instead of the string, and how can I avoid this to write better and more elegant code.

Answer 1

GET and POST objects are of class QueryDict, which is designed to deal with multiple values per key (docs).

If you are sure that you want exactly one value I would suggest

request.GET.get('expr', [])[:1]

This falls back to empty array in case ‘expr’ is not available, but this should be idiomatic Python anyway, as [] has Boolean value of False.