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<div class="example" id="time-formatting-parsing">
<h2><a href="./">Go by Example</a>: Time Formatting / Parsing</h2>
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<p>Go supports time formatting and parsing via
pattern-based layouts.</p>
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<div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
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<div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
<span class="kn">import</span> <span class="s">&quot;time&quot;</span>
</pre></div>
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<div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">p</span> <span class="o">:=</span> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span>
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<p>Here&rsquo;s a basic example of formatting a time
according to RFC3339.</p>
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<div class="highlight"><pre> <span class="nx">t</span> <span class="o">:=</span> <span class="nx">time</span><span class="p">.</span><span class="nx">Now</span><span class="p">()</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">t</span><span class="p">.</span><span class="nx">Format</span><span class="p">(</span><span class="s">&quot;2006-01-02T15:04:05Z07:00&quot;</span><span class="p">))</span>
</pre></div>
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<p><code>Format</code> uses an example-based layout approach; it
takes a formatted version of the reference time
<code>Mon Jan 2 15:04:05 MST 2006</code> to determine the
general pattern with which to format the given
time. Here are a few more examples of time
formatting.</p>
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<div class="highlight"><pre> <span class="nx">p</span><span class="p">(</span><span class="nx">t</span><span class="p">.</span><span class="nx">Format</span><span class="p">(</span><span class="s">&quot;3:04PM&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">t</span><span class="p">.</span><span class="nx">Format</span><span class="p">(</span><span class="s">&quot;Mon Jan _2 15:04:05 2006&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">t</span><span class="p">.</span><span class="nx">Format</span><span class="p">(</span><span class="s">&quot;2006-01-02T15:04:05.999999-07:00&quot;</span><span class="p">))</span>
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<p>For purely numeric representations you can also
use standard string formatting with the extracted
components of the time value.</p>
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<div class="highlight"><pre> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Printf</span><span class="p">(</span><span class="s">&quot;%d-%02d-%02dT%02d:%02d:%02d-00:00\n&quot;</span><span class="p">,</span>
<span class="nx">t</span><span class="p">.</span><span class="nx">Year</span><span class="p">(),</span> <span class="nx">t</span><span class="p">.</span><span class="nx">Month</span><span class="p">(),</span> <span class="nx">t</span><span class="p">.</span><span class="nx">Day</span><span class="p">(),</span>
<span class="nx">t</span><span class="p">.</span><span class="nx">Hour</span><span class="p">(),</span> <span class="nx">t</span><span class="p">.</span><span class="nx">Minute</span><span class="p">(),</span> <span class="nx">t</span><span class="p">.</span><span class="nx">Second</span><span class="p">())</span>
</pre></div>
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<p>Time parsing uses the same example-based approach
as <code>Format</code>ing. These examples parse times rendered
with some of the layouts used above.</p>
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<div class="highlight"><pre> <span class="nx">withNanos</span> <span class="o">:=</span> <span class="s">&quot;2006-01-02T15:04:05.999999999-07:00&quot;</span>
<span class="nx">t1</span><span class="p">,</span> <span class="nx">e</span> <span class="o">:=</span> <span class="nx">time</span><span class="p">.</span><span class="nx">Parse</span><span class="p">(</span>
<span class="nx">withNanos</span><span class="p">,</span>
<span class="s">&quot;2012-11-01T22:08:41.117442+00:00&quot;</span><span class="p">)</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">t1</span><span class="p">)</span>
<span class="nx">kitchen</span> <span class="o">:=</span> <span class="s">&quot;3:04PM&quot;</span>
<span class="nx">t2</span><span class="p">,</span> <span class="nx">e</span> <span class="o">:=</span> <span class="nx">time</span><span class="p">.</span><span class="nx">Parse</span><span class="p">(</span><span class="nx">kitchen</span><span class="p">,</span> <span class="s">&quot;8:41PM&quot;</span><span class="p">)</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">t2</span><span class="p">)</span>
</pre></div>
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<p><code>Parse</code> will return an error on malformed input
explaining the parsing problem.</p>
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<div class="highlight"><pre> <span class="nx">ansic</span> <span class="o">:=</span> <span class="s">&quot;Mon Jan _2 15:04:05 2006&quot;</span>
<span class="nx">_</span><span class="p">,</span> <span class="nx">e</span> <span class="p">=</span> <span class="nx">time</span><span class="p">.</span><span class="nx">Parse</span><span class="p">(</span><span class="nx">ansic</span><span class="p">,</span> <span class="s">&quot;8:41PM&quot;</span><span class="p">)</span>
<span class="nx">p</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span>
</pre></div>
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<p>There are several predefined formats that you can
use for both formatting and parsing.</p>
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<div class="highlight"><pre> <span class="nx">p</span><span class="p">(</span><span class="nx">t</span><span class="p">.</span><span class="nx">Format</span><span class="p">(</span><span class="nx">time</span><span class="p">.</span><span class="nx">Kitchen</span><span class="p">))</span>
<span class="p">}</span>
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<div class="highlight"><pre><span class="gp">$</span> go run <span class="nb">time</span>-formatting-parsing.go
<span class="go">2012-11-02T09:35:03-07:00</span>
<span class="go">9:35AM</span>
<span class="go">Fri Nov 2 09:35:03 2012</span>
<span class="go">2012-11-02T09:35:03.982519-07:00</span>
<span class="go">2012-11-02T09:35:03-00:00</span>
<span class="go">0001-01-01 00:00:00 +0000 UTC</span>
<span class="go">0000-01-01 20:41:00 +0000 UTC</span>
<span class="go">parsing time &quot;8:41PM&quot; as &quot;Mon Jan _2 15:04:05 2006&quot;: ...</span>
<span class="go">9:35AM</span>
</pre></div>
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<p class="next">
Next example: <a href="random-numbers">Random Numbers</a>.
</p>
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