if index > 0: loop; else: do only once (JSON & jQuery)

Question

I have been doing some customization to this jQuery paging script I found here http://stackoverflow.com/questions/516754/paging-through-records-using-jquery

I've got the paging working nicely, and it is handling different javascript responses appropriately.

I have one problem though. The response is expecting the JSON to have an index/array.

90% of the time, I have multiple entries in my JSON, but sometimes I have only one item being returned. This results in zero entries.

Here is the code I've got

var pagedContent = {
    data: null
    ,holder: null
    ,currentIndex : 0
    ,init: function(data, holder) {
        jQuery("body").data(holder,data);
        this.holder=holder;
        this.show(0, holder); // show last
    }
    ,show: function(index, holder) {
        this.data=jQuery("body").data(holder);
        if(!this.data){
          return;
        }
        var j=2;
        if(this.data.length-index<=j){
          j=this.data.length-index-1;
        }
        var jsonObj = this.data[index];
        if(!jsonObj) {
          return;
        }
        var holdSubset="";
        for(i=0;i<=j;i++){
          jsonObj=this.data[index+i];
          this.currentIndex = index;
          if(this.holder=="id1"){
            var theResultVariables = jsonObj.whatever
            var resultInput='<div class="putstuff">'+theResultVariables+'</div>';
          }
          if(this.holder=="id2"){
            var theResultVariables = jsonObj.whatever
            var resultInput='<div class="putstuff2">'+theResultVariables+'</div>';
          }
          holdSubset= holdSubset+resultInput;
        }

        jQuery("body").html("<div id=\"counter\">"+parseFloat(index+1)+" to "+ parseFloat(index+j+1)+" of "+this.data.length+"</div>"+holdSubset+"<div class=\"prevNext\"></div>");

        if(index!=0){
          var previous = jQuery("<a >").attr("href","#").click(this.previousHandler).text("< previous").data("whichList",this.holder).data("thisIndex",index - 2-1);
          jQuery("body").append(previous);
        }

        if(index+i<this.data.length){
          var next = jQuery("<a class=\"next\">").attr("href","#").click(this.nextHandler).text("next >").data("whichList",this.holder).data("thisIndex",index + 2 +1);
          jQuery("body").append(next);
        }
    }
    ,nextHandler: function() {
        pagedContent.show(jQuery(this).data("thisIndex"), jQuery(this).data("whichList"));
        return false;
    }
    ,previousHandler: function() {
        pagedContent.show(jQuery(this).data("thisIndex"), jQuery(this).data("whichList"));
        return false
    }
};

I know that I can add another check

var jsonObj = this.data[index];
if(!jsonObj){
  var jsonObj=this.data;
}
if(!jsonObj) {
  return;
}

and then lower down

jsonObj=this.data[index+i];
if(!jsonObj){
  jsonObj=this.data;
}

But I don't think that is probably the most efficient way to do it. Any ideas?

Answer 1

Since you're using jQuery, take a look at jQuery.makeArray. It takes an array or a scalar, and returns an array. If you add a call like this in as a preceding step:

this.data = jQuery.makeArray(this.data);

You won't have to worry about if it's a scalar or an array. Scalars will be converted to arrays of length 1.