2014-03-07 208 views
0

我需要有人来解释,当你点击“重置”在网页的底部如何下面的代码重置单选按钮空白几部分解释代码

任何帮助将appriciated,我相当新的JavaScript和HTML

这里与它小提琴 - http://jsfiddle.net/jamiepollard28/sDLV4/8/

<html> 
<head> 
<title>Exam entry</title> 
<script language="javascript" type="text/javascript"> 
window.onload=function(){ 
window.validateForm=function() { 
    var result = true; 
    var msg = ""; 
    var focusname=""; 
    if (document.ExamEntry.name.value == "") { 
     msg += "You must enter your name \n"; 
     focusname="name"; 
     //document.ExamEntry.name.focus(); 
     document.getElementById('name1').style.color = "red"; 
     //result = false; 
    } 
    if (document.ExamEntry.subject.value == "") { 
     msg += "You must enter the subject \n"; 
     // document.ExamEntry.subject.focus(); 
     if (focusname=="") 
     { 
     focusname="subject"; 
     } 
     document.getElementById('subject1').style.color = "red"; 
     //result = false; 
    } 
    var Number = document.ExamEntry.Exam_Number.value 
    if (Number == "") { 
     msg += "You must enter the exam Number \n"; 
     //document.ExamEntry.Exam_Number.focus(); 
     if (focusname=="") 
     { 
     focusname="Exam_Number"; 
     } 
     document.getElementById('Exam_Number1').style.color = "red"; 
     //result = false; 
    }else if (Number.length != 4) { 
     msg += "You must enter at least Four Numbers in the Exam Number \n"; 
     if (focusname=="") 
     { 
     focusname="Exam_Number"; 
     } 
     //document.ExamEntry.Exam_Number.focus(); 
     document.getElementById('Exam_Number1').style.color = "red"; 
     //result = false; 
    } 
else if (isNaN(Number)) { 
     msg += "You must enter at least four numeric characters in the Exam Number feild \n"; 
    if (focusname=="") 
     { 
     focusname="Exam_Number"; 
     } 
    // document.ExamEntry.Exam_Number.focus(); 
     document.getElementById('Exam_Number1').style.color = "red"; 
     //result = false; 
    } 
    var valchecked = ''; 
    var len = document.getElementsByName('examtype').length; 

    for (i = 0; i < len; i++) { 

if (document.ExamEntry.examtype[i].checked) { 

valchecked = document.ExamEntry.examtype[i].value; 
break; 

} 

} 
    if (valchecked == '') { 
     msg += "Select Exam Type"; 
     document.getElementById('Exam_Type').style.color = "red"; 
     if (focusname=="") 
     { 
     focusname="examtype_GCSE"; 
     } 

    } 

    if (msg != ""){ 
     alert(msg) 
     document.getElementById(focusname).focus(); 
     return false; 
    }else{ 
     return confirm('You have chosen ' + valchecked + ' is this correct?'); 
    } 

} 
}//]]> 

</script> 


</head> 
<body> 
    <h1>Exam Entry Form</h1> 
<form name="ExamEntry" method="post" action="success.html"> 
<table width="50%" border="0"> 
<tr> 
<td id="name1">Name</td> 
<td><input type="text" name="name" id="name" /></td> 
</tr> 
<tr> 
<td id="subject1">Subject</td> 
<td><input type="text" name="subject" id="subject"/></td> 
</tr> 
<tr> 
<td id="Exam_Number1">Exam Number</td> 
<td><input type="text" name="Exam_Number" id="Exam_Number" ><font size="3">(Maximum characters: 4)</font> </td> 
</tr> 
<tr> 

<table><form action=""> 
<td id="Exam_Type">Exam Type</td> 
<tr><td><input type="radio" id="examtype_GCSE" name="examtype" value="GCSE" /> : GCSE<br /></tr> 
<tr><td><input type="radio" id="examtype_AS" name="examtype" value="AS"/> : AS<br /></tr> 
<tr><td><input type="radio" id="examtype_A2" name="examtype" value="A2" /> : A2<br /></tr> 
<tr><td><input type="submit" name="Submit" value="Submit" onclick="return validateForm();" /></td> 
<td><input type="reset" name="Reset" value="Reset" /></td> 
</tr> 
</table> 
</form> 

</body> 


</html> 
+7

这不是代码。这是一个''。浏览器只知道该怎么做。 – Butt4cak3

回答

3

<input type="reset" />是一个内置的HTML表单功能。它将简单地清除或形成字段,并将其他控件设置回默认值。

0

<input type="reset" />就干脆清除所有输入值

很简单,就是从按键复位,并内置功能

0

复位按钮的属性是所有的值设置为空白正如你在创建页面时所做的那样。它不包含用户在填写表单时填充的值,并且在单选按钮的情况下,如果你放入任何参数,如选中/取消选中,那么它将会将其重置为该条件。

 <input type="radio" checked /> 

重置将清除所有表单元素,就像提交表单中的内置属性一样,重置将被重新设置。

<input type="reset"/> 
-1

Reset对象表示HTML表单中的重置按钮。

单击重置按钮可将表格中的所有控件重置为默认值。

对于HTML表单中的每个标签,都会创建一个Reset对象。

点击重置按钮会触发onreset事件!