JSLINQ Forum Rss Feed

New Post: WildCards

crpietschmann — Fri, 22 Mar 2013 22:16:50 GMT

This is out of the scope of jslinq. What you are looking for is a "startsWith" method for JavaScript strings. A simple Google search will yield many results.

New Post: WildCards

samanis — Tue, 02 Oct 2012 10:15:36 GMT

Is there any wildcard available in the product? How are we able to run a query like

Select Employees.Name from Employees where Employees.Name like 'S%' (returns all employees which their name starts with S)

New Post: When it is necessary to add .ToArray() at end of a query? also intermittently get problems with variables being "undefined"....

PatrickCodePlex — Mon, 27 Feb 2012 22:18:31 GMT

Hi, and thanks for very much for creating JSLINQ, it is a great idea and from what I have seen so far appears to be very good.

However, and this may be due more to my lack of familiarty with javasript rather than JSLINQ per se but I would be grateful for any advice/comments on the following:

(1) It's not clear to me from the documentation when .ToArray() needs to be added to the end of a JSLINQ query, e.g.

var arrayforselectedIndex = JSLINQ(viewModel.fullChartData())

.Where(function(item) { return item.Name == viewModel.selectedIndex(); })

.OrderBy(function(item) { return item.MonthEndDate; }).ToArray();

At first I omitted the .ToArray() at the end, but then I seemed to get intermittent (i.e. not always) errors when trying to access a property of one of the results of the query, e.g.

arrayforselectedIndex [0].MyProperty (where I know that all results from the query are members of the same class which has a MyProperty property.

(2) Similarly, I sometimes get "variable is undefined" errors when trying to access the results of a JSLINQ query. Any suggestions?

Thank you

got

New Post: Random() function request

crpietschmann — Mon, 25 Oct 2010 14:08:40 GMT

Thanks for the suggestion. A ".Random" method has been implemented in the code, and will be in the next update release.

http://jslinq.codeplex.com/workitem/7419

New Post: Intellisense issue

crpietschmann — Mon, 25 Oct 2010 13:40:51 GMT

Thanks for pointing this out. This has been added to the source code and will be included in the next update release.

Sorry it took almost a year for me to get this in there.

New Post: search nested array

crpietschmann — Mon, 25 Oct 2010 12:10:45 GMT

You just need to write a nested query. Below is the example that I just added to the SDK Samples.

var sample = JSLINQ(Samples.People).
            Where(function (item, index) {
                return JSLINQ(item.BookIDs)
                    .Where(function (item) { return item == 1002 })
                    .Count() > 0;
            });

Sorry for the long delayed reply.

New Post: JSLINQ Object Vs Array.Prototype

crpietschmann — Mon, 25 Oct 2010 11:48:07 GMT

JSLINQ resides in its own object so that it does not conflict with any other javascript frameworks you might be using. This is the same reason that jQuery resides completely within its own "jQuery" object instead of extending the core javascript objects with certain functionality.

New Post: search nested array

soloper — Mon, 28 Jun 2010 16:09:49 GMT

Hi just checking out jslinq for the first time -

Wondering how a search would be done to return results based on bookIDs given the sample data below i.e. select all entries that have a bookID of 1002

Samples.People = [
    { ID: 1, FirstName: "Chris", LastName: "Pearson", BookIDs: [1001, 1002, 1003] },
    { ID: 2, FirstName: "John", LastName: "Ronald", BookIDs: [4001, 4002, 4003] },
    { ID: 3, FirstName: "Steve", LastName: "Pinkerton", BookIDs: [1001, 1002, 1003] },
    { ID: 4, FirstName: "Bernard", LastName: "Sutherland", BookIDs: [1001, 2002, 3003] },
    { ID: 5, FirstName: "Kate", LastName: "Pinkerton", BookIDs: [4001, 3002, 2003] }
];

New Post: JSLint Cleanup

blueonion — Tue, 13 Apr 2010 20:47:09 GMT

I see you've made some of these changes already in the recent builds. The main link is still pointing to older code.

New Post: JSLint Cleanup

blueonion — Tue, 13 Apr 2010 20:40:40 GMT

Ran the code through JSLint. Also fixed some minor issues with the use of "new".

//-----------------------------------------------------------------------
// Part of the LINQ to JavaScript (JSLINQ) v2.10 Project - http://jslinq.codeplex.com
// Copyright (C) 2009 Chris Pietschmann (http://pietschsoft.com). All rights reserved.
// This project is licensed under the Microsoft Reciprocal License (Ms-RL)
// This license can be found here: http://jslinq.codeplex.com/license
//-----------------------------------------------------------------------
(function() {
    JSLINQ = window.JSLINQ = function(dataItems) {
        return new JSLINQ.fn.init(dataItems);
    };
    JSLINQ.fn = JSLINQ.prototype = {
        init: function(dataItems) {
            this.items = dataItems;
        },

        // The current version of JSLINQ being used
        jslinq: "2.10",

        ToArray: function() { return this.items; },
        Where: function(clause) {
            var newArray = [];

            // The clause was passed in as a Method that return a Boolean
            for (var index = 0; index < this.items.length; index++) {
                if (clause(this.items[index], index)) {
                    newArray[newArray.length] = this.items[index];
                }
            }
            return JSLINQ(newArray);
        },
        Select: function(clause) {
            var newArray = [];

            // The clause was passed in as a Method that returns a Value
            for (var i = 0; i < this.items.length; i++) {
                var result = clause(this.items[i]);
                if (result) {
                    newArray[newArray.length] = result;
                }
            }
            return JSLINQ(newArray);
        },
        OrderBy: function(clause) {
            var tempArray = [];
            for (var i = 0; i < this.items.length; i++) {
                tempArray[tempArray.length] = this.items[i];
            }
            return JSLINQ(tempArray.sort(function(a, b) {
                var x = clause(a);
                var y = clause(b);
                return ((x < y) ? -1 : ((x > y) ? 1 : 0));
            })
        );
        },
        OrderByDescending: function(clause) {
            var tempArray = [];
            for (var i = 0; i < this.items.length; i++) {
                tempArray[tempArray.length] = this.items[i];
            }
            return JSLINQ(tempArray.sort(function(a, b) {
                var x = clause(b);
                var y = clause(a);
                return ((x < y) ? -1 : ((x > y) ? 1 : 0));
            })
        );
        },
        SelectMany: function(clause) {
            var r = [];
            for (var i = 0; i < this.items.length; i++) {
                r = r.concat(clause(this.items[i]));
            }
            return JSLINQ(r);
        },
        Count: function(clause) {
            return (clause === null || clause === undefined) ? this.items.length : this.Where(clause).items.length;
        },
        Distinct: function(clause) {
            var item;
            var dict = {};
            var retVal = [];
            for (var i = 0; i < this.items.length; i++) {
                item = clause(this.items[i]);
                // TODO - This doens't correctly compare Objects. Need to fix this
                if (dict[item] === null || dict[item] === undefined) {
                    dict[item] = true;
                    retVal[retVal.length] = item;
                }
            }
            dict = null;
            return JSLINQ(retVal);
        },
        Any: function(clause) {
            for (var index = 0; index < this.items.length; index++) {
                if (clause(this.items[index], index)) { return true; }
            }
            return false;
        },
        All: function(clause) {
            for (var index = 0; index < this.items.length; index++) {
                if (!clause(this.items[index], index)) { return false; }
            }
            return true;
        },
        Reverse: function() {
            var retVal = [];
            for (var index = this.items.length - 1; index > -1; index--) {
                retVal[retVal.length] = this.items[index];
            }
            return JSLINQ(retVal);
        },
        First: function(clause) {
            if (clause !== null && clause !== undefined) {
                return this.Where(clause).First();
            }
            // If no clause was specified, then return the First element in the Array
            return (this.items.length > 0) ? this.items[0] : null;
        },
        Last: function(clause) {
            if (clause !== null && clause !== undefined) {
                return this.Where(clause).Last();
            }
            // If no clause was specified, then return the First element in the Array
            return (this.items.length > 0) ? this.items[this.items.length - 1] : null;
        },
        ElementAt: function(index) {
            return this.items[index];
        },
        Concat: function(array) {
            var arr = array.items || array;
            return JSLINQ(this.items.concat(arr));
        },
        Intersect: function(secondArray, clause) {
            var clauseMethod = (clause !== undefined) ? clause
                : function(item, index, item2, index2) { return item === item2; };

            var sa = secondArray.items || secondArray;
            var result = [];

            for (var a = 0; a < this.items.length; a++) {
                for (var b = 0; b < sa.length; b++) {
                    if (clauseMethod(this.items[a], a, sa[b], b)) {
                        result[result.length] = this.items[a];
                    }
                }
            }
            return JSLINQ(result);
        },
        DefaultIfEmpty: function(defaultValue) {
            return (this.items.length === 0) ? defaultValue : this;
        },
        ElementAtOrDefault: function(index, defaultValue) {
            return (index >= 0 && index < this.items.length) ? this.items[index] : defaultValue;
        },
        FirstOrDefault: function(defaultValue) {
            return this.First() || defaultValue;
        },
        LastOrDefault: function(defaultValue) {
            return this.Last() || defaultValue;
        }
    };
    JSLINQ.fn.init.prototype = JSLINQ.fn;
})();

New Post: JSLINQ Object Vs Array.Prototype

Drahcir — Sun, 07 Feb 2010 01:14:09 GMT

Before I ask my question I just want to say; really nice job with this project. It's simple, elegant, and makes a lot of JavaScript developers lives a lot easier!

Now onto the question.
I'm curious to know why you decided to use a new object, "JSLINQ", rather then 'extend' on the existing Array object using the prototype approach? This question isn't an insult on your approach because it works, I was just wondering if you had considered the .prototype approach, and then for some reason changed your mind?

keep up the good works.

New Post: Intellisense issue

homam — Mon, 30 Nov 2009 07:02:12 GMT

I have to add this line

/// <returns type="JSLINQ" />

at the end of constructor function in JSLINQ-vsdoc.js to work in my version of VS 2008.

New Post: Random() function request

homam — Mon, 30 Nov 2009 06:34:39 GMT

I always add this function to JSLINQ:

Random: function() {
            var len = this.items.length;
            var index = parseInt((Math.random() * len));
            return this.items[index];
        }

I think it might be useful in many scenarios and it can be added to the official version of JSLINQ.

Thanks!

New Post: Select calls clause function twice

crpietschmann — Tue, 16 Jun 2009 23:06:34 GMT

Thanks. This has been fixed.

New Post: A Better Query Tool Than jQuery?

crpietschmann — Tue, 16 Jun 2009 22:59:02 GMT

I just added (in v2.10) a plugin model to JSLINQ that is similar to JQuery via adding methods to "JSLINQ.fn". If you are interested in adding your own plugins to JSLINQ, there is a simple example located within the release download.

New Post: Select calls clause function twice

cshipley — Sun, 10 May 2009 16:10:00 GMT

Out of curiosity, in the Select method, why not call the clause function once, then if the result evaluates to true, add it to the array? This would roughly double performance of select.

So, from:

for (var i = 0; i < this.items.length; i++) {
if (clause(this.items[i])) {
newArray[newArray.length] = clause(this.items[i]);
}
}

To this:

for (var i = 0; i < this.items.length; i++) {

var result = clause(this.items[i]);
if (result)
newArray[newArray.length] = result;
}

-- Curtis

New Post: JSLINQ better approach

crpietschmann — Mon, 30 Mar 2009 22:03:38 GMT

I would be interested in seeing the code you wrote if you're willing to share it. Please post it somewhere and post a link here. Thanks.

New Post: JSLINQ better approach

galsoftware — Tue, 09 Dec 2008 08:51:42 GMT

Hello. I think I have a much better approach about how to implement a LINQ-like library in javascript. First of all, remember that you must define functions to give the option for joining multiple arrays. (inner join, left join, right join). I just started coding my library, and after I wrote more then 80K of code i found your library on codeplex. But I AM SURE that my library is far more better than yours. I use lambda expressions, FULL LINQ-like syntax, I have "groupping", "having", "Inner/Left/Right JOIN", etc :) If anybody is interested about my library you can write to me at aurelian.lica (at) gmail.com

New Post: JSLINQ and LIKE Operation?

crpietschmann — Wed, 15 Oct 2008 06:02:10 GMT

JSLINQ doesn't include a LIKE operator since that is really something that needs to be done within the Where method anyway. In order to perform a LIKE operation, you'll need to place the logic for it within the clause (or closure) that you pass the Where method.

New Post: No client side dependency

crpietschmann — Wed, 15 Oct 2008 05:57:46 GMT

JSLINQ.js is completely self contained. It requires no other JavaScript Frameworks on the client, and works cross-browser. Also since it is a JavaScript library, it does not have any dependence on the .NET Framework.