javascript – 如何使标签可见/不可见？

我有这些日期和时间字段,我想设置一个 JavaScript验证的时间.

如果格式无效,它应该使标签可见,否则它应该是不可见的.

这是迄今为止的代码.

<td nowrap="nowrap" align="left">
            <table border="0" cellpadding="0" cellspacing="0">
                <tr>
                    <td align="right" nowrap="nowrap">
                        <span id="startDateLabel">Start date/time: </span>
                        <input id="startDateStr" name="startDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
                        <button id="startDateCalendarTrigger">...</button>
                        <input id="startDateTime" type="text" size="8" name="startTime" value="12:00 AM" onchange="validateHHMM(this.value);"/>
                        <label id="startTimeLabel" visible="false">Time must be entered in the format HH:MM AM/PM</label>
                        <BR>
                        <span id="endDateLabel">End date/time: </span>
                        <input id="endDateStr" name="endDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
                        <button id="endDateCalendarTrigger">...</button>
                        <input id="endDateTime" type="text" size="8" name="endTime" value="12:00 AM" onchange="validateHHMM2(this.value);"/>
                        <label id="endTimeLabel" visible="false">Time must be entered in the format HH:MM AM/PM</label>
                    </td>
                </tr>
            </table>
        </td>

问题是标签在加载时显示,无论我设置为可见.我尝试了可见度=“隐藏”,它仍然显示.

这是验证部分：

<script>
function validateHHMM(inputField) {
    var isValid = /^(0?[1-9]|1[012])(:[0-5]\d) [APap][mM]$/.test(inputField.value);
 
    if (isValid) {
        document.getElementById("startTimeLabel").style.visibility = "hidden";
    }else {
        document.getElementById("startTimeLabel").style.visibility = "visible";
    }
 
    return isValid;
}
function validateHHMM2(inputField) {
    var isValid = /^(0?[1-9]|1[012])(:[0-5]\d) [APap][mM]$/.test(inputField.value);
 
    if (isValid) {
        document.getElementById("endTimeLabel").style.visibility = "hidden";
    }else {
        document.getElementById("endTimeLabel").style.visibility = "visible";
    }
 
    return isValid;
}
 </script>

那么我该怎么办呢？ Google显示不同的验证方法,但不显示如何隐藏/显示标签

解决方法

您正在寻找显示：

document.getElementById("endTimeLabel").style.display = 'none';
document.getElementById("endTimeLabel").style.display = 'block';

编辑：您也可以轻松地重用验证功能.

HTML：

<span id="startDateLabel">Start date/time: </span>
<input id="startDateStr" name="startDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
<button id="startDateCalendarTrigger">...</button>
<input id="startDateTime" type="text" size="8" name="startTime" value="12:00 AM" onchange="validateHHMM(this.value,'startTimeLabel');"/>
<label id="startTimeLabel" class="errorMsg">Time must be entered in the format HH:MM AM/PM</label><br />
 
<span id="endDateLabel">End date/time: </span>
<input id="endDateStr" name="endDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
<button id="endDateCalendarTrigger">...</button>
 
<input id="endDateTime" type="text" size="8" name="endTime" value="12:00 AM" onchange="validateHHMM(this.value,'endTimeLabel');"/>
<label id="endTimeLabel" class="errorMsg">Time must be entered in the format HH:MM AM/PM</label>

使用Javascript：

function validateHHMM(value,message) {
    var isValid = /^(0?[1-9]|1[012])(:[0-5]\d) [APap][mM]$/.test(value);
 
    if (isValid) {
        document.getElementById(message).style.display = "none";
    }else {
        document.getElementById(message).style.display= "inline";
    }
 
    return isValid;
}

Live DEMO

javascript – 如何使标签可见/不可见？

解决方法

猜你在找的JavaScript相关文章