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    <p>The easiest way to do this, with excellent performance and compatibility with both old and new browsers, is to include either <a href="http://lodash.com/" rel="noreferrer">Lo-Dash</a> or <a href="http://underscorejs.org/" rel="noreferrer">Underscore</a> in your page.</p> <p>Then you can use either <code>_.size(object)</code> or <code>_.keys(object).length</code></p> <p>For your <code>obj.Data</code>, you could test this with:</p> <pre><code>console.log( _.size(obj.Data) ); </code></pre> <p>or:</p> <pre><code>console.log( _.keys(obj.Data).length ); </code></pre> <p>Lo-Dash and Underscore are both excellent libraries; you would find either one very useful in your code. (They are rather similar to each other; Lo-Dash is a newer version with some advantanges.)</p> <p>Alternatively, you could include this function in your code, which simply loops through the object's properties and counts them:</p> <pre><code>function ObjectLength( object ) { var length = 0; for( var key in object ) { if( object.hasOwnProperty(key) ) { ++length; } } return length; }; </code></pre> <p>You can test this with:</p> <pre><code>console.log( ObjectLength(obj.Data) ); </code></pre> <p>That code is not as fast as it could be in modern browsers, though. For a version that's much faster in modern browsers and still works in old ones, you can use:</p> <pre><code>function ObjectLength_Modern( object ) { return Object.keys(object).length; } function ObjectLength_Legacy( object ) { var length = 0; for( var key in object ) { if( object.hasOwnProperty(key) ) { ++length; } } return length; } var ObjectLength = Object.keys ? ObjectLength_Modern : ObjectLength_Legacy; </code></pre> <p>and as before, test it with:</p> <pre><code>console.log( ObjectLength(obj.Data) ); </code></pre> <p>This code uses <code>Object.keys(object).length</code> in modern browsers and falls back to counting in a loop for old browsers.</p> <p>But if you're going to all this work, I would recommend using Lo-Dash or Underscore instead and get all the benefits those libraries offer.</p> <p>I set up a <a href="http://jsperf.com/counting-object-properties" rel="noreferrer">jsPerf that compares the speed of these various approaches</a>. Please run it in any browsers you have handy to add to the tests.</p> <p>Thanks to <a href="https://stackoverflow.com/users/1491895/barmar">Barmar</a> for <a href="https://stackoverflow.com/a/16976940/1202830">suggesting <code>Object.keys</code> for newer browsers</a> in his answer.</p>
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    1. POJavascript counting number of objects in object
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    1. USMichael Geary
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    1. COUsing the conditional operator to do this kind of feature-detection seems overly complicated.
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      1. USPaul Phillips
    2. COHi, can you explain on this? Can I put this into a function and call whenever we need it? For safe precaution to users who use older browser, I will try to adopt this.
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      1. USBryan Learn
    3. COIt's a pretty common way to do it, but fair enough, you could easily do the same thing with an if statement. The main thing is to do it outside the function instead of inside the function.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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