blocks|key|2428840|text|您可以使用qrand创建随机数。如果需要字符串，可以将int转换为string。您还可以检查QUuid类，它生成通用惟一标识符。这些不是“完全随机的”，但它们是独一无二的。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2428841|entityMap|0|LINK|mutability|MUTABLE|url|http://doc.qt.io/qt-5/qtglobal.html#qrand|1|http://doc.qt.io/qt-5/quuid.html^0|5|5|0|1A|5|1|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]|$A|R|B|S|1|T]]|C|$]]|$1|D|3|-4|5|6|7|U|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]|L|$5|G|H|I|C|$J|M]]]]

You can create random numbers using <a href="http://doc.qt.io/qt-5/qtglobal.html#qrand" rel="noreferrer">qrand</a>. If you need strings, you can convert the int to string. You could also check the <a href="http://doc.qt.io/qt-5/quuid.html" rel="noreferrer">QUuid</a> class, which generates Universally Unique Identifiers. Those are not 'totally random', but they are unique.

blocks|key|733087|text|int+number;
int+randomValue+=+qrand()+%25+number;|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|733088|返回具有0+<=+randomValue+<+number的随机数randomValue。|unstyled|offset|length|style|CODE|733089|qrand()是在QtGlobal中声明的，它被许多其他Qt文件包含。|733090|int+value;
QString+aString+=+QString::number(value);|733091|将整数转换为QString。|733092|entityMap|0|LINK|mutability|MUTABLE|url|http://qt-project.org/doc/qt-4.8/qtglobal.html#qrand|1|http://qt-project.org/doc/qt-4.8/qtglobal.html^0|0|9|B|N|6|X|B|0|0|7|0|7|0|9|8|1|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|11|8|@$G|12|H|13|I|J]|$G|14|H|15|I|J]|$G|16|H|17|I|J]]|9|@]|A|$]]|$1|K|3|L|5|F|7|18|8|@$G|19|H|1A|I|J]]|9|@$G|1B|H|1C|1|1D]|$G|1E|H|1F|1|1G]]|A|$]]|$1|M|3|N|5|6|7|1H|8|@]|9|@]|A|$B|C]]|$1|O|3|P|5|F|7|1I|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|F|7|1J|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]|Y|$5|T|U|V|A|$W|Z]]]]

<pre><code>int number;
int randomValue = qrand() % number;
</code></pre>

returns a random number <code>randomValue</code> with 0 &lt;= <code>randomValue</code> &lt; <code>number</code>.

<a href="http://qt-project.org/doc/qt-4.8/qtglobal.html#qrand" rel="noreferrer"><code>qrand()</code></a> is declared in <a href="http://qt-project.org/doc/qt-4.8/qtglobal.html" rel="noreferrer">QtGlobal</a> which is #included by many other Qt files.

<pre><code>int value;
QString aString = QString::number(value);
</code></pre>

converts an integer to QString.

blocks|key|730822|text|下面的示例生成大写字母从A到Z且长度=+len的字母字符串。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|730823|QString+randString(int+len)
{
++++QString+str;
++++str.resize(len);
++++for+(int+s+=+0;+s+<+len+;+%2B%2Bs)
++++++++str[s]+=+QChar('A'+%2B+char(qrand()+%25+('Z'+-+'A')));

++++return+str;
}|code-block|syntax|javascript|730824|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

The following example generates alphabetic strings with capital letters from A to Z and length = len.

<pre><code>QString randString(int len)
{
 QString str;
 str.resize(len);
 for (int s = 0; s &lt; len ; ++s)
 str[s] = QChar('A' + char(qrand() % ('Z' - 'A')));

 return str;
}
</code></pre>

blocks|key|1479357|text|这不是一个在给定范围内生成随机数的非常好的方法。(事实上，这对大多数生成器来说都是非常非常糟糕的)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1479358|假设来自生成器的低阶比特是均匀分布的。大多数生成器都不是这样的。在大多数生成器中，随机性发生在高位比特。|1479359|通过使用除法后的余数，你实际上是在丢弃随机性。|1479360|你应该使用乘法和除法进行缩放。不使用模运算符。例如|1479361|my_numbe+r=+start_required+%2B+(+generator_output+*++range_required)/generator_maximum;|code-block|syntax|javascript|1479362|如果generator_output在[0,+generator_maximum]中，那么my_number将在[start_required+,+start_required++%2B+range_required]中。|offset|length|style|CODE|1479363|entityMap^0|0|0|0|0|0|2|G|J|M|19|9|1K|1F|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|X|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|Y|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|Z|8|@$O|10|P|11|Q|R]|$O|12|P|13|Q|R]|$O|14|P|15|Q|R]|$O|16|P|17|Q|R]]|9|@]|A|$]]|$1|S|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|T|$]]

This is not a very good method to generate random numbers within a given range. (In fact it's very very bad for most generators )

You are assuming that the low-order bits from the generator are uniformly distributed. This is not the case with most generators. In most generators the randomness occurs in the high order bits.

By using the remainder after divisions you are in effect throwing out the randomness.

You should scale using multiplication and division. Not using the modulo operator.
eg

<pre><code>my_numbe r= start_required + ( generator_output * range_required)/generator_maximum;
</code></pre>

If <code>generator_output</code> is in <code>[0, generator_maximum]</code>, 
<code>my_number</code> will be in <code>[start_required , start_required + range_required]</code>.

blocks|key|733152|text|使用qrand()时，Here是一个很好的答案。下面的解决方案使用上面已经建议的QUuid来生成随机和唯一的ids+(它们都是hex数字)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|733153|#include+<QApplication>
#include+<QDebug>
#include+<QRegularExpression>
#include+<QUuid>

int+main(int+argc,+char+*argv[])
{
++++QApplication+a(argc,+argv);

++++//+random+hex+string+generator
++++for+(int+i+=+0;+i+<+10;+i%2B%2B)
++++{
++++++++QString+str+=+QUuid::createUuid().toString();
++++++++str.remove(QRegularExpression("{%7C}%7C-"));+//+if+you+want+only+hex+numbers
++++++++qDebug()+<<+str;
++++}

++++return+a.exec();
}|code-block|syntax|javascript|733154|输出|BOLD|733155|"479a494a852747fe90efe0dc0137d059"
"2cd7e3b404b54fad9154e46c527c368a"
"84e43735eacd4b8f8d733bf642476097"
"d7e824f920874f9d8b4264212f3bd385"
"40b1c6fa89254705801caefdab5edd96"
"b7067852cf9d45ca89dd7af6ffdcdd23"
"9a2e5e6b65c54bea8fb9e7e8e1676a1a"
"981fa826073947e68adc46ddf47e311c"
"129b0ec42aed47d78be4bfe279996990"
"818035b0e83f401d8a56f34122ba7990"|733156|entityMap|0|LINK|mutability|MUTABLE|url|http://doc.qt.io/qt-5/qtglobal.html#qrand|1|https://stackoverflow.com/a/18866593/6407320|2|http://doc.qt.io/qt-5/quuid.html^0|1R|3|2|7|0|B|4|1|14|5|2|0|0|0|2|0|0^^$0|@$1|2|3|4|5|6|7|11|8|@$9|12|A|13|B|C]]|D|@$9|14|A|15|1|16]|$9|17|A|18|1|19]|$9|1A|A|1B|1|1C]]|E|$]]|$1|F|3|G|5|H|7|1D|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1E|8|@$9|1F|A|1G|B|M]]|D|@]|E|$]]|$1|N|3|O|5|H|7|1H|8|@]|D|@]|E|$I|J]]|$1|P|3|-4|5|6|7|1I|8|@]|D|@]|E|$]]]|Q|$R|$5|S|T|U|E|$V|W]]|X|$5|S|T|U|E|$V|Y]]|Z|$5|S|T|U|E|$V|10]]]]

<a href="https://stackoverflow.com/a/18866593/6407320">Here</a> is the good answer using <a href="http://doc.qt.io/qt-5/qtglobal.html#qrand" rel="nofollow noreferrer">qrand()</a>. The solution below uses <a href="http://doc.qt.io/qt-5/quuid.html" rel="nofollow noreferrer">QUuid</a>, as already was suggested above, to generate random and unique ids (they are all <code>hex</code> numbers):

<pre><code>#include &lt;QApplication&gt;
#include &lt;QDebug&gt;
#include &lt;QRegularExpression&gt;
#include &lt;QUuid&gt;

int main(int argc, char *argv[])
{
 QApplication a(argc, argv);

 // random hex string generator
 for (int i = 0; i &lt; 10; i++)
 {
 QString str = QUuid::createUuid().toString();
 str.remove(QRegularExpression("{|}|-")); // if you want only hex numbers
 qDebug() &lt;&lt; str;
 }

 return a.exec();
}
</code></pre>

Output

<pre><code>"479a494a852747fe90efe0dc0137d059"
"2cd7e3b404b54fad9154e46c527c368a"
"84e43735eacd4b8f8d733bf642476097"
"d7e824f920874f9d8b4264212f3bd385"
"40b1c6fa89254705801caefdab5edd96"
"b7067852cf9d45ca89dd7af6ffdcdd23"
"9a2e5e6b65c54bea8fb9e7e8e1676a1a"
"981fa826073947e68adc46ddf47e311c"
"129b0ec42aed47d78be4bfe279996990"
"818035b0e83f401d8a56f34122ba7990"
</code></pre>

blocks|key|1476338|text|使用QUuid|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1476339|#include+<QUuid>
QString+randomStr+=+QUuid::createUuid();|code-block|syntax|javascript|1476340|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Use QUuid

<pre><code>#include &lt;QUuid&gt;
QString randomStr = QUuid::createUuid();
</code></pre>

Is there any function or something like that by which I can create totally random strings or numbers?

Create a random string or number in Qt4

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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有没有什么函数或类似的函数可以让我创建完全随机的字符串或数字？

问在Qt4中创建随机字符串或数字
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回答 6

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问在Qt4中创建随机字符串或数字
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