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POShould I Overload == Operator?
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  1. POShould I Overload == Operator?
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    copied!<p>How does the <code>==</code> operator really function in C#? If it used to compare objects of class <em>A</em>, will it try to match all of <em>A</em>'s properties, or will it look for pointers to the same memory location (or maybe something else)?</p> <p>Let's create a hypothetical example. I'm writing an application that utilizes the Twitter API, and it has a <em>Tweet</em> class, which has all the properties of a single tweet: text, sender, date&amp;time, source, etc. If I want to compare objects of class <em>Tweet</em> for equivalence, can I just use:</p> <pre><code>Tweet a, b; if (a == b) { //do something... } </code></pre> <p>Will that <strong>check for equivalence of all the properties</strong> of the <em>Tweet</em> class between <em>a</em> and <em>b</em>?</p> <p>If not, <strong>would the correct approach be to overload the <code>==</code> operator</strong> to explicitly check for equivalence of all the fields?</p> <p><strong>UPDATE:</strong> From the first two answers, am I right in assuming:</p> <ul> <li>If the <code>==</code> operator or <em>Equals</em> method is not overloaded for a class, the <code>==</code> operator for the <em>object</em> class is used.</li> <li>The <code>==</code> operator for the <em>object</em> class checks for equality in memory location.</li> <li>I have to overload the <code>==</code> operator or the <em>Equals</em> method to accomplish this task.</li> <li>In the overload, I have to check for equivalence in properties manually, so <strong>there is no way to do it semi-automatically, say, in a loop</strong>, right?</li> </ul> <p><strong>UPDATE #2:</strong> Yuriy made a comment that it is possible to do check for equivalence in properties in the <code>==</code> operator with <strong>reflection</strong>. How can this be done? Could you give me some sample code? Thanks!</p>
 

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