Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p><strong>Update:</strong> Turns out that this method, while following STL idioms well, is actually surprisingly inefficient! Don't do this with large files. (See: <a href="http://insanecoding.blogspot.com/2011/11/how-to-read-in-file-in-c.html" rel="noreferrer">http://insanecoding.blogspot.com/2011/11/how-to-read-in-file-in-c.html</a>)</p> <p>You can make a streambuf iterator out of the file and initialize the string with it:</p> <pre><code>#include &lt;string&gt; #include &lt;fstream&gt; #include &lt;streambuf&gt; std::ifstream t("file.txt"); std::string str((std::istreambuf_iterator&lt;char&gt;(t)), std::istreambuf_iterator&lt;char&gt;()); </code></pre> <p>Not sure where you're getting the <code>t.open("file.txt", "r")</code> syntax from. As far as I know that's not a method that <code>std::ifstream</code> has. It looks like you've confused it with C's <code>fopen</code>.</p> <p><strong>Edit:</strong> Also note the extra parentheses around the first argument to the string constructor. <em>These are essential</em>. They prevent the problem known as the "<a href="http://web.archive.org/web/20110426155617/http://www.informit.com/guides/content.aspx?g=cplusplus&amp;seqNum=439" rel="noreferrer">most vexing parse</a>", which in this case won't actually give you a compile error like it usually does, but will give you interesting (read: wrong) results.</p> <p>Following KeithB's point in the comments, here's a way to do it that allocates all the memory up front (rather than relying on the string class's automatic reallocation):</p> <pre><code>#include &lt;string&gt; #include &lt;fstream&gt; #include &lt;streambuf&gt; std::ifstream t("file.txt"); std::string str; t.seekg(0, std::ios::end); str.reserve(t.tellg()); t.seekg(0, std::ios::beg); str.assign((std::istreambuf_iterator&lt;char&gt;(t)), std::istreambuf_iterator&lt;char&gt;()); </code></pre>
    singulars
    1. This table or related slice is empty.
    1. PORead whole ASCII file into C++ std::string
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USresueman
    1. USTyler McHenry
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PORead whole ASCII file into C++ std::string
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COopen is definitely a method of ifstream, however the 2nd parameter is wrong. http://www.cplusplus.com/reference/iostream/ifstream/open/
      singulars
      1. PO
      1. USJoe
    2. CORight. I was saying that `ifstream` doesn't have a method with the signature `open(const char*, const char*)`
      singulars
      1. PO
      1. USTyler McHenry
    3. COThis is just making the explicit loop implicit. Since the iterator is a forward iterator, it will be read one character at a time. Also, since there is no way for the string constructor to know the final length, it will probably lead to several allocations and copies of the data.
      singulars
      1. PO
      1. USKeithB
 

Querying!

 
Guidance
A row detail

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.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload