<form id='theForm'>
<label>Field 1:
<input type='text' value='provide a value for field 1'>
</label>
<br><label>Field 2:
<input type='text' value='provide a value for field 2'>
</label>
<br><label>Field 3:
<input type='text' value='provide a value for field 3'>
</label>
</form>
使用 jQuery 的 JavaScript:
jQuery(function($) {
// Save the initial values of the inputs as placeholder text
$('#theForm input').attr("data-placeholdertext", function() {
return this.value;
});
// Hook up a handler to delete the placeholder text on focus,
// and put it back on blur
$('#theForm')
.delegate('input', 'focus', function() {
if (this.value === $(this).attr("data-placeholdertext")) {
this.value = '';
}
})
.delegate('input', 'blur', function() {
if (this.value.length == 0) {
this.value = $(this).attr("data-placeholdertext");
}
});
});
<form id='theForm'>
<label>Field 1:
<input type='text' placeholder='provide a value for field 1'>
</label>
<br><label>Field 2:
<input type='text' placeholder='provide a value for field 2'>
</label>
<br><label>Field 3:
<input type='text' placeholder='provide a value for field 3'>
</label>
</form>
使用 jQuery 的 JavaScript:
jQuery(function($) {
// Is placeholder supported?
if ('placeholder' in document.createElement('input')) {
// Yes, no need for us to do it
display("This browser supports automatic placeholders");
}
else {
// No, do it manually
display("Manual placeholders");
// Set the initial values of the inputs as placeholder text
$('#theForm input').val(function() {
if (this.value.length == 0) {
return $(this).attr('placeholder');
}
});
// Hook up a handler to delete the placeholder text on focus,
// and put it back on blur
$('#theForm')
.delegate('input', 'focus', function() {
if (this.value === $(this).attr("placeholder")) {
this.value = '';
}
})
.delegate('input', 'blur', function() {
if (this.value.length == 0) {
this.value = $(this).attr("placeholder");
}
});
}
function display(msg) {
$("<p>").html(msg).appendTo(document.body);
}
});
$("selector").data("DefaultText", SetYourDefaultTextHere);
// You can also define the DefaultText as attribute and access that using attr() function
$("selector").focus(function(){
if($(this).val() == $(this).data("DefaultText"))
$(this).val('');
});
**//Click The Button**
$('#yourButton').click(function(){
**//What you want to do with your button**
//YOUR CODE COMES HERE
**//CLEAR THE INPUT**
$('#yourInput').val('');
});
首先,用 jQuery 选择按钮:
$('#button').click(function((){ //Then you get the input element $('#input')
//Then you clear the value by adding:
.val(' '); });