Javascript – Reading the list items Sharepoint 2010 client object model

javascriptsharepointsharepoint-2010sharepoint-api

I have a list where I am storing the image URLs and I am trying to read list of items and display the images on the page. For that I wrote the script something like below….

<script type="text/javascript">
    function ViewItem()
    {
        var myQueryString = '<Query><Where><Eq><FieldRef Name="Anchor" /><Value 

Type="Boolean">1</Value></Eq></Where></Query>'; 

        var context = new SP.ClientContext.get_current();
        var web = context.get_web();
        var list = web.get_lists().getByTitle('AnchorImageList');
        var myquery = new SP.CamlQuery();

        myquery.set_viewXml(myQueryString); 

        myItems = list.getItems(myquery);


        context.load(myItems, 'Include(Title,ImageURL)');
        context.executeQueryAsync(Function.createDelegate(this, this.success), 

Function.createDelegate(this, this.failed));
    }
    function success() 
    {

        var LinkURL= "";
        var ImageURL="";
        var ListEnumerator = this.myItems.getEnumerator();
        while(ListEnumerator.moveNext())
        {
            var currentItem = ListEnumerator.get_current();
            LinkURL = currentItem.get_item('Title') ;
            ImageURL= currentItem.get_item('ImageURL');
            document.write('<img src="' + ImageURL+ '"+>');
            alert(LinkURL);

        }

    }
    function failed(sender, args) 
    {
        alert("failed. Message:" + args.get_message());
    }
</script>
<a href="#" onclick="Javascript:ViewItem();">View Items</a>

In my CAML query I am trying to filter items which are tagged yes for "Anchor?"(yes/no column).

But I am seeing all the results even though I tagged few items not to display. What I am doing wrong here. Please someone help me. Also,after the images are loaded on the page, the page is still showing the wheel as if it is processing something. Do I need to do something for this?

Best Answer

try this one:

<View>
  <Query>
    <Where>
      <Eq>
        <FieldRef Name="Anchor" />
        <Value Type="Boolean">1</Value>
      </Eq>
    </Where>
  </Query>
</View>

in case if it doesn't work for you, follow next steps:

Create a list view using standard functionality.
Open it at SharePoint Designier and just copy CAML query from the code.

Hope this will help.

Native deep cloning

It's called "structured cloning", works experimentally in Node 11 and later, and hopefully will land in browsers. See this answer for more details.

Fast cloning with data loss - JSON.parse/stringify

If you do not use Dates, functions, undefined, Infinity, RegExps, Maps, Sets, Blobs, FileLists, ImageDatas, sparse Arrays, Typed Arrays or other complex types within your object, a very simple one liner to deep clone an object is:

JSON.parse(JSON.stringify(object))

const a = {
  string: 'string',
  number: 123,
  bool: false,
  nul: null,
  date: new Date(),  // stringified
  undef: undefined,  // lost
  inf: Infinity,  // forced to 'null'
  re: /.*/,  // lost
}
console.log(a);
console.log(typeof a.date);  // Date object
const clone = JSON.parse(JSON.stringify(a));
console.log(clone);
console.log(typeof clone.date);  // result of .toISOString()

See Corban's answer for benchmarks.

Reliable cloning using a library

Since cloning objects is not trivial (complex types, circular references, function etc.), most major libraries provide function to clone objects. Don't reinvent the wheel - if you're already using a library, check if it has an object cloning function. For example,

lodash - cloneDeep; can be imported separately via the lodash.clonedeep module and is probably your best choice if you're not already using a library that provides a deep cloning function
AngularJS - angular.copy
jQuery - jQuery.extend(true, { }, oldObject); .clone() only clones DOM elements
just library - just-clone; Part of a library of zero-dependency npm modules that do just do one thing. Guilt-free utilities for every occasion.

ES6 (shallow copy)

For completeness, note that ES6 offers two shallow copy mechanisms: Object.assign() and the spread syntax. which copies values of all enumerable own properties from one object to another. For example:

var A1 = {a: "2"};
var A2 = Object.assign({}, A1);
var A3 = {...A1};  // Spread Syntax

Javascript – How to efficiently count the number of keys/properties of an object in JavaScript

To do this in any ES5-compatible environment, such as Node.js, Chrome, Internet Explorer 9+, Firefox 4+, or Safari 5+:

Object.keys(obj).length

Browser compatibility
Object.keys documentation (includes a method you can add to non-ES5 browsers)

Best Answer

Related Solutions

Javascript – the most efficient way to deep clone an object in JavaScript

Native deep cloning

Fast cloning with data loss - JSON.parse/stringify

Reliable cloning using a library

ES6 (shallow copy)

Javascript – How to efficiently count the number of keys/properties of an object in JavaScript

Related Topic