Javascript 如何使用innerHTML显示多个输出?
我在脚本中有这个函数Javascript 如何使用innerHTML显示多个输出?,javascript,Javascript,我在脚本中有这个函数 function arith() { var n1 = parseInt(document.getElementById('num1').value, 10); var n2 = parseInt(document.getElementById('num2').value, 10); var newVal; if(op == "Operation 1") { newVal1 = n1 + n2; } e
function arith()
{
var n1 = parseInt(document.getElementById('num1').value, 10);
var n2 = parseInt(document.getElementById('num2').value, 10);
var newVal;
if(op == "Operation 1")
{
newVal1 = n1 + n2;
}
else if(op == "Operation 2")
{
newVal2 = n1 - n2;
}
else if(op == "Operation 3")
{
newVal3 = n1 * n2;
}
else if(op == "Operation 4")
{
newVal4 = n1 / n2;
}
var demoP = document.getElementById("demo");
{
demoP.innerHTML = "Operation 1=" + newVal1;
demoP.innerHTML = "Operation 2=" + newVal2;
demoP.innerHTML = "Operation 3=" + newVal3;
demoP.innerHTML = "Operation 4=" + newVal4;
}
return false;
}
当我调用这些innerHTML时,我可以使用
足够了吗,或者我需要调用每个元素?调用
innerHtml
将覆盖每次调用的内容。在分配给innerHTML
属性之前,在字符串中构建HTML
var demoP = document.getElementById("demo");
{
var html = "";
html += "Operation 1=" + newVal1 + "<br/>";
html += "Operation 2=" + newVal2 + "<br/>";
html += "Operation 3=" + newVal3 + "<br/>";
html += "Operation 4=" + newVal4 + "<br/>";
demoP.innerHTML = html;
}
var demo=document.getElementById(“demo”);
{
var html=“”;
html+=“操作1=“+newVal1+”
;
html+=“操作2=“+newVal2+”
”;
html+=“操作3=“+newVal3+”
;
html+=“操作4=“+newVal4+”
”;
deop.innerHTML=html;
}
JS Fiddle:调用innerHtml
将覆盖每次调用的内容。在分配给innerHTML
属性之前,在字符串中构建HTML
var demoP = document.getElementById("demo");
{
var html = "";
html += "Operation 1=" + newVal1 + "<br/>";
html += "Operation 2=" + newVal2 + "<br/>";
html += "Operation 3=" + newVal3 + "<br/>";
html += "Operation 4=" + newVal4 + "<br/>";
demoP.innerHTML = html;
}
var demo=document.getElementById(“demo”);
{
var html=“”;
html+=“操作1=“+newVal1+”
;
html+=“操作2=“+newVal2+”
”;
html+=“操作3=“+newVal3+”
;
html+=“操作4=“+newVal4+”
”;
deop.innerHTML=html;
}
JS Fiddle:当前代码首先将元素的.innerHTML
设置为“Operation 1=“+newVal1
,然后用其他值覆盖它三次。也许您打算将所有结果连接在一起,并将结果放在该元素中:
demoP.innerHTML = "Operation 1=" + newVal1 + "<br>"
+ "Operation 2=" + newVal2 + "<br>"
+ "Operation 3=" + newVal3 + "<br>"
+ "Operation 4=" + newVal4;
deop.innerHTML=“操作1=“+newVal1+”
”
+“操作2=“+newVal2+”
”
+“操作3=“+newVal3+”
”
+“操作4=“+newVal4;
当前代码首先将元素的.innerHTML
设置为“操作1=“+newVal1
,然后用其他值覆盖它三次。也许您打算将所有结果连接在一起,并将结果放在该元素中:
demoP.innerHTML = "Operation 1=" + newVal1 + "<br>"
+ "Operation 2=" + newVal2 + "<br>"
+ "Operation 3=" + newVal3 + "<br>"
+ "Operation 4=" + newVal4;
deop.innerHTML=“操作1=“+newVal1+”
”
+“操作2=“+newVal2+”
”
+“操作3=“+newVal3+”
”
+“操作4=“+newVal4;
您应该使用+=
而不是=
,否则它将覆盖您的数据
demoP.innerHTML += "Operation 2=" + newVal2;
调用一次就足够了。您应该使用+=
而不是=
,否则它会重写您的数据
demoP.innerHTML += "Operation 2=" + newVal2;
调用一次就足够了。最好的方法是在最后一刻连接字符串并添加到DOM(节省时间)
而且,demo后的括号是不必要的最好的方法是在最后一刻将字符串合并并添加到DOM中(节省时间)
此外,演示后的括号是不必要的只需一行即可:
demoP.innerHTML = "Operation 1=" + newVal1 + "<br>"+ "Operation 2=" + newVal2 + "<br>"+ "Operation 3=" + newVal3 + "<br>"+"Operation 4=" + newVal4;
deop.innerHTML=“操作1=“+newVal1+”
“+”操作2=“+newVal2+”
“+”操作3=“+newVal3+”
“+”操作4=“+newVal4;
您只需一行:
demoP.innerHTML = "Operation 1=" + newVal1 + "<br>"+ "Operation 2=" + newVal2 + "<br>"+ "Operation 3=" + newVal3 + "<br>"+"Operation 4=" + newVal4;
deop.innerHTML=“操作1=“+newVal1+”
“+”操作2=“+newVal2+”
“+”操作3=“+newVal3+”
“+”操作4=“+newVal4;
注意,四个newValX
变量中只有一个在该函数中被赋值(因为if/else if结构)。它们是全局变量吗?如果它们没有在某个地方声明,当您尝试使用尚未赋值的变量时,将出现引用错误。请注意,在该函数中,四个newValX
变量中只有一个将被赋值(因为If/else If结构)。它们是全局变量吗?如果它们没有在某个地方声明,那么当您尝试使用尚未赋值的引用时,将出现引用错误。