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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head>  <meta name="generator" content=  "HTML Tidy for Linux/x86 (vers 1 September 2005), see www.w3.org">  <title>getline</title>  <link href="../cppreference.css" rel="stylesheet" type="text/css"></head><body><table>  <tr>  <td>  <div class="body-content">  <div class="header-box">    <a href="../index.html">cppreference.com</a> &gt; <a href=    "index.html">C++ Strings</a> &gt; <a href=    "getline.html">getline</a>  </div>  <div class="name-format">    getline  </div>  <div class="syntax-name-format">    Syntax:  </div>  <pre class="syntax-box">  #include &lt;string&gt;  istream&amp; getline( istream&amp; is, string&amp; s, char delimiter = &#39;\n&#39; );</pre>  <p>The C++ string class defines the global function getline() to read  strings from an I/O stream. The getline() function, which is not  part of the string class, reads a line from <em>is</em> and stores it  into <em>s</em>. If a character <em>delimiter</em> is specified, then  getline() will use <em>delimiter</em> to decide when to stop reading  data.</p>  <p>For example, the following code reads a line of text from  <strong>stdin</strong> and displays it to  <strong>stdout</strong>:</p>  <pre class="example-code"> string s; getline( cin, s ); cout &lt;&lt; &quot;You entered &quot; &lt;&lt; s &lt;&lt; endl;</pre>  <p>After getting a line of data in a string, you may find that <a  href="../cppsstream/index.html">string streams</a> are useful in extracting  data from that string.  For example, the following code reads  numbers from standard input, ignoring any "commented" lines that  begin with double slashes:</p>  <pre class="example-code">  // expects either space-delimited numbers or lines that start with  // two forward slashes (//)  string s;  while( getline(cin,s) ) {    if( s.size() >= 2 && s[0] == '/' && s[1] == '/' ) {      cout << "  ignoring comment: " << s << endl;    } else {      istringstream ss(s);      double d;      while( ss >> d ) {        cout << "  got a number: " << d << endl;      }    }  }</pre>  <p>When run with a user supplying input, the above code might  produce this output:</p>  <pre class="example-code">  // test    ignoring comment: // test  23.3 -1 3.14159    got a number: 23.3    got a number: -1    got a number: 3.14159  // next batch    ignoring comment: // next batch  1 2 3 4 5    got a number: 1    got a number: 2    got a number: 3    got a number: 4    got a number: 5  50    got a number: 50</pre>  <div class="related-name-format">    Related topics:  </div>  <div class="related-content">    (C++ I/O) <a href="../cppio/get.html">get</a><br>    (C++ I/O) <a href="../cppio/getline.html">getline</a><br>    <a href="../cppsstream/index.html">string streams</a>  </div>  </div>  </td>    </tr>  </table></body></html>
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