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<div class="example" id="string-functions">
<h2><a href="./">Go by Example</a>: String Functions</h2>
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<p>The standard library&rsquo;s <code>strings</code> package provides many
useful string-related functions. Here are some examples
to give you a sense of the package.</p>
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<div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>
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<div class="highlight"><pre><span class="kn">import</span> <span class="nx">s</span> <span class="s">&quot;strings&quot;</span>
<span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
</pre></div>
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<p>We alias <code>fmt.Println</code> to a shorter name as we&rsquo;ll use
it a lot below.</p>
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<div class="highlight"><pre><span class="kd">var</span> <span class="nx">p</span> <span class="p">=</span> <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</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>
</pre></div>
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<p>Here&rsquo;s a sample of the functions available in
<code>strings</code>. Note that these are all functions from
package, not methods on the string object itself.
This means that we need pass the string in question
as the first argument to the function.</p>
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<div class="highlight"><pre> <span class="nx">p</span><span class="p">(</span><span class="s">&quot;Contains: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Contains</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="s">&quot;es&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Count: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Count</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="s">&quot;t&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;HasPrefix: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">HasPrefix</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="s">&quot;te&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;HasSuffix: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">HasSuffix</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="s">&quot;st&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Index: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Index</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">,</span> <span class="s">&quot;e&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Join: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Join</span><span class="p">([]</span><span class="kt">string</span><span class="p">{</span><span class="s">&quot;a&quot;</span><span class="p">,</span> <span class="s">&quot;b&quot;</span><span class="p">},</span> <span class="s">&quot;-&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Repeat: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Repeat</span><span class="p">(</span><span class="s">&quot;a&quot;</span><span class="p">,</span> <span class="mi">5</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Replace: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Replace</span><span class="p">(</span><span class="s">&quot;foo&quot;</span><span class="p">,</span> <span class="s">&quot;o&quot;</span><span class="p">,</span> <span class="s">&quot;0&quot;</span><span class="p">,</span> <span class="o">-</span><span class="mi">1</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Replace: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Replace</span><span class="p">(</span><span class="s">&quot;foo&quot;</span><span class="p">,</span> <span class="s">&quot;o&quot;</span><span class="p">,</span> <span class="s">&quot;0&quot;</span><span class="p">,</span> <span class="mi">1</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Split: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">Split</span><span class="p">(</span><span class="s">&quot;a-b-c-d-e&quot;</span><span class="p">,</span> <span class="s">&quot;-&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;toLower: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">ToLower</span><span class="p">(</span><span class="s">&quot;TEST&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;ToUpper: &quot;</span><span class="p">,</span> <span class="nx">s</span><span class="p">.</span><span class="nx">ToUpper</span><span class="p">(</span><span class="s">&quot;test&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">()</span>
</pre></div>
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<p>You can find more functions in the <a href="http://golang.org/pkg/strings/"><code>strings</code></a>
package docs.</p>
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<p>Not part of <code>strings</code> but worth mentioning here are
the mechanisms for getting the length of a string
and getting a character by index.</p>
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<div class="highlight"><pre> <span class="nx">p</span><span class="p">(</span><span class="s">&quot;Len: &quot;</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="s">&quot;hello&quot;</span><span class="p">))</span>
<span class="nx">p</span><span class="p">(</span><span class="s">&quot;Char:&quot;</span><span class="p">,</span> <span class="s">&quot;hello&quot;</span><span class="p">[</span><span class="mi">1</span><span class="p">])</span>
<span class="p">}</span>
</pre></div>
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<div class="highlight"><pre><span class="gp">$</span> go run string-functions.go
<span class="go">Contains: true</span>
<span class="go">Count: 2</span>
<span class="go">HasPrefix: true</span>
<span class="go">HasSuffix: true</span>
<span class="go">Index: 1</span>
<span class="go">Join: a-b</span>
<span class="go">Repeat: aaaaa</span>
<span class="go">Replace: f00</span>
<span class="go">Replace: f0o</span>
<span class="go">Split: [a b c d e]</span>
<span class="go">toLower: test</span>
<span class="go">ToUpper: TEST</span>
</pre></div>
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<div class="highlight"><pre><span class="go">Len: 5</span>
<span class="go">Char: 101</span>
</pre></div>
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<p class="next">
Next example: <a href="string-formatting">String Formatting</a>.
</p>
<p class="footer">
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