How do I submit an name[] array with Ajax?

Today's development comes across a problem: How does jquery's Ajax commit an [name][] array? It is well known that the name plus [] can directly transfer the array to the server, but Ajax does not work, directly using name[] will directly error.

Example:

        $.ajax ({            URL: "${ctx}/addcart",            type: "Post",            data:{"name[]": $ (". pid"). Val ()},            DataType: "Text",            traditional:true,            success:function (data) {                if (data! = "0") {                    $ (". Cartlist span"). Text (Number ($ ("). Cartlist span "). Text ()) +number (data));                    Showbo.Msg.alert ("added to Cart");                else{                    window.location.href= "${ctx}/login";}}        )

The great God suggests that you can serialize a form to commit

        $.ajax ({            URL: "${ctx}/addcart",
Cache:true,            type: "Post",            data:$ (' #yourformid '). Serialize (),            dataType: "Text",            traditional:true,            success:function (data) {                if (data! = "0") {                    $ (". Cartlist span"). Text (Number ($ (". Cartlist span"). Text ()) + Number (data));                    Showbo.Msg.alert ("added to Cart");                else{                    window.location.href= "${ctx}/login";}}        )

And then the egg, still reported 400

My way of handling:

        $.each ($ (". pid"). Serializearray (), Function (i, field) {            Pid.push (field.value);        });        $.ajax ({            URL: "${ctx}/addcart",            type: "Post",            data:{pid:pid},            dataType: "Text",            traditional: True,            success:function (data) {                if (data! = "0") {                    $ (". Cartlist span"). Text (Number ($ (". Cartlist span"). Text ()) +number (data));                    Showbo.Msg.alert ("added to Cart");                else{                    window.location.href= "${ctx}/login";}}        )    }

Actually very fascinated, do not know why add the brackets on the hehe

How do I submit an name[] array with Ajax?