uTools-Manuals/docs/c/isalpha.html

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<h1>字符函数 - isalpha</h1>
<p>原型extern int isalpha(int c);</p>
<p>用法:#include &lt;ctype.h></p>
<p>功能判断字符c是否为英文字母</p>
<p>说明当c为英文字母a-z或A-Z时返回非零值否则返回零</p>
举例:
<pre><code class="language-c">
// isalpha.c
#include &lt;syslib.h>
#include &lt;ctype.h>
#include &lt;stdio.h>
main()
{
int c;
clrscr(); // clear screen
printf("Press a key");
for(;;)
{
c=getchar();
clrscr();
printf("%c: %s letter",c,isalpha(c)?"is":"not");
}
return 0; // just to avoid warnings by compiler
}
</code></pre>
相关函数:<a href="isalnum.html">isalnum</a>,<a href="isdigit.html">isdigit</a>,<a href="isxdigit.html">isxdigit</a>,<a href="iscntrl.html">iscntrl</a>,<a href="isgraph.html">isgraph</a>,<a href="isprint.html">isprint</a>,<a href="ispunct.html">ispunct</a>,<a href=isspace.html">isspace</a>