我们上课的任务是输入整数。我们不知道会有多少。
我想知道是否可以格式化scanf函数，该函数存储整数或通过按Enter终止自身。
我能以某种方式将仅存储整数的scanf("%d")和终止scanf("%[^\n])函数的scanf放在一起吗？
我所知道的是我不能使用scanf("%d%[^\n])，因为scanf正在等待那个整数，我不想输入，因为我已经存储了所有必须的整数。 / p>
我真的不喜欢将所有这些整数的字符串存储到数组中，然后将其转换为具有精确数字的另一个数组的元素的可能性。
答案 0 :(得分：1)
扫描一个字符。跳过空间和制表符。在换行符上退出。
删除最近的字符，然后尝试扫描整数。如果无法扫描整数，请扫描并丢弃非数字，空格键和换行符除外。
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
.dropbtn{background-color:white;color:black;padding:4px;font-size:18px;border:none;cursor:pointer;border-radius: 7px;border: 2px solid #008CBA;-webkit-transition-duration: 0.8s; /* Safari */
transition-duration: 0.8s;
}.dropbtn:focus,.dropbtn:hover{background-color:#4db8ff}#myInput{border-box:box-sizing;background-image:url(searchicon.png);background-position:14px 12px;background-repeat:no-repeat;font-size:16px;padding:14px 20px 12px 45px;border:none;border-bottom:1px solid #ddd}#myInput:focus{outline:#ddd solid 3px}.Country{position:relative;display:inline-block}.Country-content{display:none;position:absolute;background-color:#f6f6f6;min-width:230px;overflow:auto;border:1px solid #ddd;z-index:1}.Country-content a{color:#000;padding:12px 16px;text-decoration:none;display:block}.Country a:hover{background-color:#ddd}.show{display:block}
}
#myInput {
border-box: box-sizing;
background-image: url('searchicon.png');
background-position: 14px 12px;
background-repeat: no-repeat;
font-size: 16px;
padding: 14px 20px 12px 45px;
border: none;
border-bottom: 1px solid #ddd;
}
#myInput:focus {outline: 3px solid #ddd;}
.Country {
position: relative;
display: inline-block;
}
.Country-content {
display: none;
position: absolute;
background-color: #f6f6f6;
min-width: 230px;
overflow: auto;
border: 1px solid #ddd;
z-index: 1;
}
.Country-content a {
color: black;
padding: 12px 16px;
text-decoration: none;
display: block;
}
.Country a:hover {background-color: #ddd;}
.show {display: block;}
</style>
</head>
<body>
<div class="Country">
<button onclick="myFunction()" class="dropbtn">Country</button>
<div id="myCountry" class="Country-content">
<input type="text" placeholder="Search here..." id="myInput" onkeyup="filterFunction()">
<select size="20">
<option><a href="/professional-network/asia/Afghanistan">[flag=af] <span>Afghanistan</span></a>
<option><a href="/professional-network/asia/Armenia">[flag=am] <span>Armenia</span></a>
<option><a href="/professional-network/asia/Azerbaijan">[flag=az] <span>Azerbaijan</span></a>
<option><a href="/professional-network/asia/Bahrain">[flag=bh] <span>Bahrain</span></a>
<option><a href="/professional-network/asia/Bangladesh">[flag=bd] <span>Bangladesh</span></a>
<option><a href="/professional-network/asia/Bhutan">[flag=bt] <span>Bhutan</span></a>
<option><a href="/professional-network/asia/Brunei">[flag=bn] <span>Brunei</span></a>
<option><a href="/professional-network/asia/Cambodia">[flag=kh] <span>Cambodia</span></a></option>
<option><a href="/professional-network/asia/Cyprus">[flag=cy] <span>Cyprus</span></a></option>
<option><a href="/professional-network/asia/East Timor">[flag=tl] <span>East Timor</span></a></option>
<option><a href="/professional-network/asia//Georgia">[flag=ge] <span>Georgia</span></a></option>
<option><a href="/professional-network/asia/India">[flag=in] <span>India</span></a></option>
<option><a href="/professional-network/asia/Indonesia">[flag=id] <span>Indonesia</span></a></option>
<option><a href="/professional-network/asia/Iran">[flag=ir] <span>Iran</span></a></option>
<option><a href="/professional-network/asia/Iraq">[flag=iq] <span>Iraq</span></a></option>
<option><a href="/professional-network/asia/Israel">[flag=il] <span>Israel</span></a></option>
<option><a href="/professional-network/asia/Japan">[flag=jp] <span>Japan</span></a></option>
<option><a href="/professional-network/asia/Jordan">[flag=jo] <span>Jordan</span></a></option>
<option><a href="/professional-network/asia/Kazakhstan">[flag=kz] <span>Kazakhstan</span></a></option>
<option><a href="/professional-network/asia/Kuwait">[flag=kw] <span>Kuwait</span></a></option>
<option><a href="/professional-network/asia/Kyrgyzstan">[flag=kg] <span>Kyrgyzstan</span></a></option>
<option><a href="/professional-network/asia/Laos">[flag=la] <span>Laos</span></a></option>
<option><a href="/professional-network/asia/Lebanon">[flag=lb] <span>Lebanon</span></a></option>
<option><a href="/professional-network/asia/Malaysia">[flag=my] <span>Malaysia</span></a></option>
<option><a href="/professional-network/asia/Maldives">[flag=mv] <span>Maldives</span></a></option>
<option><a href="/professional-network/asia/Mongolia">[flag=mn] <span>Mongolia</span></a></option>
<option><a href="/professional-network/asia/Myanmar">[flag=mm] <span>Myanmar</span></a></option>
<option><a href="/professional-network/asia/Nepal">[flag=np] <span>Nepal</span></a></option>
<option><a href="/professional-network/asia/North Korea">[flag=kp] <span>North Korea</span></a></option>
<option><a href="/professional-network/asia/Oman">[flag=om] <span>Oman</span></a></option>
<option><a href="/professional-network/asia/Pakistan">[flag=pk] <span>Pakistan</span></a></option>
<option><a href="/professional-network/asia/China">[flag=cn] <span>China</span></a></option>
<option><option><a href="/professional-network/asia/The Philippines">[flag=ph] <span>The Philippines</span></a></option>
<option><a href="/professional-network/asia/Qatar">[flag=qa] <span>Qatar</span></a></option>
<option><a href="/professional-network/asia/Taiwan">[flag=tw] <span>Taiwan</span></a></option>
<option><a href="/professional-network/asia/Russia">[flag=ru] <span>Russia</span></a></option>
<option><a href="/professional-network/asia/Saudi Arabia">[flag=sa] <span>Saudi Arabia</span></a></option>
<option><a href="/professional-network/asia/Singapore">[flag=sg] <span>Singapore</span></a></option>
<option><a href="/professional-network/asia/China">[flag=sg] <span>China</span></a></option>
<option><a href="/professional-network/asia/South Korea">[flag=kr] <span>South Korea</span></a></option>
<option><a href="/professional-network/asia/Sri Lanka">[flag=lk] <span>Sri Lanka</span></a></option>
<option><a href="/professional-network/asia/Syria">[flag=sy] <span>Syria</span></a></option>
<option><a href="/professional-network/asia/Tajikistan">[flag=tj] <span>Tajikistan</span></a></option>
<option><a href="/professional-network/asia/Thailand">[flag=th] <span>Thailand</span></a></option>
<option><a href="/professional-network/asia/The United Arab Emirates">[flag=ae] <span>The United Arab Emirates</span></a></option>
<option><a href="/professional-network/asiaTurkey">[flag=tr] <span>Turkey</span></a></option>
<option><a href="/professional-network/asia/Turkmenistan">[flag=tm] <span>Turkmenistan</span></a></option>
<option><a href="/professional-network/asia/Uzbekistan">[flag=uz] <span>Uzbekistan</span></a></option>
<option><a href="/professional-network/asia/Vietnam">[flag=vn] <span>Vietnam</span></a></option>
<option><a href="/professional-network/asia/Yemen">[flag=ye] <span>Yemen</span></a>
</div>
</div>
<script>
function myFunction() {
document.getElementById("myCountry").classList.toggle("show");
}
function filterFunction() {
var input, filter, ul, li, a, i;
input = document.getElementById("myInput");
filter = input.value.toUpperCase();
div = document.getElementById("myCountry");
a = div.getElementsByTagName("a");
for (i = 0; i < a.length; i++) {
var label = a[i].querySelector('span');
if (label.innerText.toUpperCase().indexOf(filter) > -1) {
a[i].style.display = "";
} else {
a[i].style.display = "none";
}
}
}
</script>
</body>
</html>答案 1 :(得分：1)
scanf函数难以正确使用。
相反，使用fgets一次读取一行。如果输入的字符串只是换行符，则退出循环。如果不是，请使用strtol解析值。您将知道，如果结束指针指向输入末尾的换行符，那么是否仅输入了整数。
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
int main()
{
char line[100], *p;
long val;
while (fgets(line, sizeof(line), stdin)) {
// if enter was pressed by itself, quit loop
if (!strcmp(line, "\n")) {
break;
}
errno = 0;
val = strtol(line, &p, 10);
if (errno) {
perror("error reading value");
} else if ((p != line) && (*p == '\n')) {
// a valid integer was read
printf("read value %ld\n", val);
} else {
// a non-integer was read or extra characters were entered
printf("not a valid integer: %s", line);
}
}
return 0;
}