我认为您尝试在所有浏览器中运行“占位符”。然后只需附加一个 .js 文件,它在所有浏览器中都可以正常工作。
;(function(window, document, $) {
var isInputSupported = 'placeholder' in document.createElement('input'),
isTextareaSupported = 'placeholder' in document.createElement('textarea'),
prototype = $.fn,
valHooks = $.valHooks,
hooks,
placeholder;
if (isInputSupported && isTextareaSupported) {
placeholder = prototype.placeholder = function() {
return this;
};
placeholder.input = placeholder.textarea = true;
} else {
placeholder = prototype.placeholder = function() {
var $this = this;
$this
.filter((isInputSupported ? 'textarea' : ':input') + '[placeholder]')
.not('.placeholder')
.bind({
'focus.placeholder': clearPlaceholder,
'blur.placeholder': setPlaceholder
})
.data('placeholder-enabled', true)
.trigger('blur.placeholder');
return $this;
};
placeholder.input = isInputSupported;
placeholder.textarea = isTextareaSupported;
hooks = {
'get': function(element) {
var $element = $(element);
return $element.data('placeholder-enabled') && $element.hasClass('placeholder') ? '' : element.value;
},
'set': function(element, value) {
var $element = $(element);
if (!$element.data('placeholder-enabled')) {
return element.value = value;
}
if (value == '') {
element.value = value;
// Issue #56: Setting the placeholder causes problems if the element continues to have focus.
if (element != document.activeElement) {
// We can't use `triggerHandler` here because of dummy text/password inputs :(
setPlaceholder.call(element);
}
} else if ($element.hasClass('placeholder')) {
clearPlaceholder.call(element, true, value) || (element.value = value);
} else {
element.value = value;
}
// `set` can not return `undefined`; see http://jsapi.info/jquery/1.7.1/val#L2363
return $element;
}
};
isInputSupported || (valHooks.input = hooks);
isTextareaSupported || (valHooks.textarea = hooks);
$(function() {
// Look for forms
$(document).delegate('form', 'submit.placeholder', function() {
// Clear the placeholder values so they don't get submitted
var $inputs = $('.placeholder', this).each(clearPlaceholder);
setTimeout(function() {
$inputs.each(setPlaceholder);
}, 10);
});
});
// Clear placeholder values upon page reload
$(window).bind('beforeunload.placeholder', function() {
$('.placeholder').each(function() {
this.value = '';
});
});
}
function args(elem) {
// Return an object of element attributes
var newAttrs = {},
rinlinejQuery = /^jQuery\d+$/;
$.each(elem.attributes, function(i, attr) {
if (attr.specified && !rinlinejQuery.test(attr.name)) {
newAttrs[attr.name] = attr.value;
}
});
return newAttrs;
}
function clearPlaceholder(event, value) {
var input = this,
$input = $(input);
if (input.value == $input.attr('placeholder') && $input.hasClass('placeholder')) {
if ($input.data('placeholder-password')) {
$input = $input.hide().next().show().attr('id', $input.removeAttr('id').data('placeholder-id'));
// If `clearPlaceholder` was called from `$.valHooks.input.set`
if (event === true) {
return $input[0].value = value;
}
$input.focus();
} else {
input.value = '';
$input.removeClass('placeholder');
input == document.activeElement && input.select();
}
}
}
function setPlaceholder() {
var $replacement,
input = this,
$input = $(input),
$origInput = $input,
id = this.id;
if (input.value == '') {
if (input.type == 'password') {
if (!$input.data('placeholder-textinput')) {
try {
$replacement = $input.clone().attr({ 'type': 'text' });
} catch(e) {
$replacement = $('<input>').attr($.extend(args(this), { 'type': 'text' }));
}
$replacement
.removeAttr('name')
.data({
'placeholder-password': true,
'placeholder-id': id
})
.bind('focus.placeholder', clearPlaceholder);
$input
.data({
'placeholder-textinput': $replacement,
'placeholder-id': id
})
.before($replacement);
}
$input = $input.removeAttr('id').hide().prev().attr('id', id).show();
// Note: `$input[0] != input` now!
}
$input.addClass('placeholder');
$input[0].value = $input.attr('placeholder');
} else {
$input.removeClass('placeholder');
}
}
}(this, document, jQuery));
然后只需将一个脚本放在页面上。
<script>
$(function() {
$('input, textarea').placeholder();
});
</script>
它在所有浏览器中都能正常工作(占位符)