javascript 如果选中复选框，则需要输入
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If checkbox selected make input required
提问by Malasorte
As part of a web form, I have two checkboxes (both with the name "my_checkbox") and two input filelds (one with the name "input1" and the other named "input2").
作为 Web 表单的一部分，我有两个复选框（均名为“my_checkbox”）和两个输入文件（一个名为“input1”，另一个名为“input2”）。
<input type="checkbox" name="my_checkbox" value="some text" onclick="a function; checkBoxValidate(0);">
<input type="checkbox" name="my_checkbox" value="some diffrent text" onclick="a diffrent function; checkBoxValidate(1);">
<input id="input1" name="input1" />
<input id="input2" name="input2" />
If user selects the first checkbox, input1 must not be empty. If user selects the second checkbox, input2 must not be empty. The two checkboxes must have the same name. Function checkBoxValidate assures the two checkboxes cannot be selected at the same time (I don't like radio buttons).
如果用户选中第一个复选框，则 input1 不得为空。如果用户选中第二个复选框，则 input2 不得为空。这两个复选框必须具有相同的名称。函数 checkBoxValidate 确保不能同时选择两个复选框（我不喜欢单选按钮）。
My javascript:
我的javascript：
}else if (!document.myform.my_checkbox[0].checked && myform.input1.value == ''){
alert ('Please enter some text!',function(){$(myform.input1).focus();});
return false;
}else if (!document.myform.my_checkbox[1].checked && myform.input2.value == ''){
alert ('Please enter some text!',function(){$(myform.input2).focus();});
return false;
Of course, nothing works! Please help? :)
当然，没有任何作用！请帮忙？:)
回答by mplungjan
Seeing you might want to take this simple, I write it simple and use plain JS since you did not tag the question with jQuery.
看到你可能想把这个简单化，我把它写得很简单并使用普通的 JS，因为你没有用 jQuery 标记问题。
window.onload=function() {
var form1=document.getElementById("form1"); // assuming <form id="form1"
form1.onsubmit=function() {
if (this.my_checkbox[0].checked && this.input1.value=="") {
alert("Please enter something in input 1");
this.input1.focus();
return false;
}
if (this.my_checkbox[1].checked && this.input2.value=="") {
alert("Please enter something in input 2");
this.input2.focus();
return false;
}
return true; // allow submission
}
// if the checkboxes had different IDs this could have been one function
form1.my_checkbox[0].onclick=function() {
this.form.my_checkbox[1].checked=!this.checked;
}
form1.my_checkbox[1].onclick=function() {
this.form.my_checkbox[0].checked=!this.checked;
}
}
回答by Kawinesh SK
HMTL
HMTL
<input type="text" id="textbox"/><br/>
<input type="checkbox" id="checkbox1" value="CB1"/><br/>
<input type="text" id="textbox1"/><br/>
<input type="checkbox" id="checkbox12"/>
JavaScript
JavaScript
$('#checkbox1').on('click',function(){
var checked=$(this).is(':checked');
if(checked==true)
{
$('#textbox1').attr('disabled',true);
$('#checkbox12').attr('checked', false);
$('#textbox').attr('disabled',false);
var text=$('#textbox').val();
checktext(text)
}
});
$('#checkbox12').on('click',function(){
var checked=$(this).is(':checked');
if(checked==true)
{
$('#textbox').attr('disabled',true);
$('#checkbox1').attr('checked', false);
$('#textbox1').attr('disabled',false);
var text=$('#textbox1').val();
checktext(text)
}
});
function checktext(text){
alert(text);
if(text=='')
alert('Enter Text');
}
