需要帮助使用innerHTML和数组输入变量 [英] Need helping with innerHTML and array input variables
问题描述
我需要这个来接受用户输入。取该值并减去一个，以便可以调用和打印5个数组中的一个。如果选择5，则打印所有5个阵列;
<！DOCTYPE html PUBLIC - // W3C // DTD XHTML1 .0Transitional // ENhttp://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">
< html xmlns =http://www.w3.org/1999/xhtml>
< head>
< meta http-equiv =Content-Typecontent =text / html; charset = utf-8/>
< title> Test2< / title>
< / head>
< body>
< input type =buttononclick =dutyarray（）value =Click>查看我的顶部< input type =numberid =counter>工作职责< /输入>
< br />
< p id =任务>职责< / p>
< script>
函数dutyarray（）
{
var x = document.getElementById（'counter'）。value;
x = parseInt（x）;
var duty = new Array（）;
税[0] =操作设备;
值[1] =检查水损坏;
duty [2] =检查模具;
税[3] =遵照保险程序;
税[4] =恢复; （x> = 0; x-1）
{
document.getElementById（'task'）。innerHTML = duty [x] +< br>;
}
}
< / script>
您可以使用
var duty = [
操作设备，
检查水损坏，
检查模具，
Follow Insurance Procedure，
Restore
]，
x = parseInt（document.getElementById（'counter'）。value，10）;
document.getElementById（'task'）。innerHTML = duty.slice（0，x）.join（'< br />'）;
注意 p>
-
使用
parseInt或<$时，始终使用第二个参数（基数） c $ c> parseFloat 。 -
如果
document.getElementById（'counter' code>是一个数字字符串（如'3'），不要使用parseInt。相反，如果需要，可以使用+'3'来获取数字3。
如果您想将
'3px'>分析为<$ c>，请仅使用parseInt不要使用getElementById来获得。$ c $> $ <$ code>。
然后，而不是
for（var i = 0; i< n; ++ i）{
doSomething（document.getElementById（'foo'），i）;
使用
var el = document.getElementById（'foo'）;
for（var i = 0; i< n; ++ i）{
doSomething（el，i）;
}
切勿更改 然后，而不是 使用 innerHTML
<$>在循环的每次迭代中，对于（var i = 0; i< n; ++ i）{
element.innerHTML + = someHTML（i）; pre $ // n DOM修改
}
var html =''; $ i $ b $ for（var i = 0; i
}
element.innerHTML = html; //只有1个DOM修改
I need this to take user input. Take the value and subtract one so that one of the 5 arrays can be called and printed. If 5 is chosen, all 5 arrays are printed; if 3 is chosen arrays 0 through 2 are printed.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML1.0Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Test2</title>
</head>
<body>
<input type="button" onclick="dutyarray()" value="Click">To see my top<input type="number" id="counter"> job duties here</input>
<br />
<p id="task">Duties</p>
<script>
function dutyarray()
{
var x = document.getElementById('counter').value;
x = parseInt(x);
var duty= new Array();
duty[0] = "Operate Equipment";
duty[1] = "Check for Water Damage";
duty[2] = "Check for Mold";
duty[3] = "Follow Insurance Procedure";
duty[4] = "Restore";
while(x >= 0; x - 1)
{
document.getElementById('task').innerHTML = duty[x] + <br>;
}
}
</script>
You could use
var duty = [
"Operate Equipment",
"Check for Water Damage",
"Check for Mold",
"Follow Insurance Procedure",
"Restore"
],
x = parseInt( document.getElementById('counter').value, 10 );
document.getElementById('task').innerHTML = duty.slice(0, x).join('<br />');
Notes
Always use the second argument (radix) when using
parseIntorparseFloat.If
document.getElementById('counter').valueis a numerical string (like'3'), don't useparseInt. Instead, if necessary, use+'3'to get the number3.Only use
parseIntif you want to parse something like'3px'into3.Don't use
getElementByIdto get the same element at each iteration of a loop.Then, instead of
for(var i = 0; i < n; ++i) { doSomething(document.getElementById('foo'), i); }use
var el = document.getElementById('foo'); for(var i = 0; i < n; ++i) { doSomething(el, i); }Never change
innerHTMLat each iteration of a loop, because modifying the DOM has bad performance.Then, instead of
for(var i = 0; i < n; ++i) { element.innerHTML += someHTML(i); // n DOM modifications }use
var html = ''; for(var i = 0; i < n; ++i) { html += someHTML(i); } element.innerHTML = html; // only 1 DOM modification
这篇关于需要帮助使用innerHTML和数组输入变量的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
