Javascript 如何检测输入文本字段中的更改并启用“保存”按钮
我试图编写一个函数,它检测文本字段中的更改并启用“保存”按钮 这是在Visual Studio 2017、HTML和JavaScript中运行的Javascript 如何检测输入文本字段中的更改并启用“保存”按钮,javascript,jquery,html,json,Javascript,Jquery,Html,Json,我试图编写一个函数,它检测文本字段中的更改并启用“保存”按钮 这是在Visual Studio 2017、HTML和JavaScript中运行的 (function () { var customer_address = localStorage.getItem("customer_address"); var customer_city = localStorage.getItem("customer_city"); var customer_postal_code
(function () {
var customer_address = localStorage.getItem("customer_address");
var customer_city = localStorage.getItem("customer_city");
var customer_postal_code = localStorage.getItem("customer_postal_code");
//Address Section
function changeAddress() {
var oldaddress = $("#txtOldAddress").val();
var newaddress = $("#txtNewAddress").val();
var url = serverURL() + "/savenewaddress.php";
var JSONObject = {
"customer_username": localStorage.getItem("customer_username"),
"oldaddress": oldaddress,
"newaddress": newaddress,
};
$.ajax({
url: url,
type: 'GET',
data: JSONObject,
dataType: 'json',
contentType: "application/json; charset=utf-8",
success: function (arr) {
_changeAddressResult(arr);
},
error: function () {
alert("FAIL");
}
});
}
function _changeAddressResult(arr) {
if (arr[0].result === 1) {
/*localStorage.setItem($("#txtNewPassword").val(), customer_username);*/
alert("OK!")
}
else {
alert("FAIL2");
}
}
//City Section
function changeCity() {
var oldcity = $("#txtOldCity").val();
var newcity = $("#txtNewCity").val();
var url = serverURL() + "/savenewcity.php";
var JSONObject = {
"customer_username": localStorage.getItem("customer_username"),
"oldcity": oldcity,
"newcity": newcity,
};
$.ajax({
url: url,
type: 'GET',
data: JSONObject,
dataType: 'json',
contentType: "application/json; charset=utf-8",
success: function (arr) {
_changeAddressResult(arr);
},
error: function () {
alert("FAIL");
}
});
}
function _changeAddressResult(arr) {
if (arr[0].result === 1) {
/*localStorage.setItem($("#txtNewPassword").val(), customer_username);*/
alert("OK!")
}
else {
alert("FAIL2");
}
}
//Postal Code Section
function changePostalCode() {
var oldpostalcode = $("#txtOldPostalCode").val();
var newpostalcode = $("#txtNewPostalCode").val();
var url = serverURL() + "/savenewpostalcode.php";
var JSONObject = {
"customer_username": localStorage.getItem("customer_username"),
"oldpostalcode": oldpostalcode,
"newpostalcode": newpostalcode
};
$.ajax({
url: url,
type: 'GET',
data: JSONObject,
dataType: 'json',
contentType: "application/json; charset=utf-8",
success: function (arr) {
_changeAddressResult(arr);
},
error: function () {
alert("FAIL");
}
});
}
function _changeAddressResult(arr) {
if (arr[0].result === 1) {
/*localStorage.setItem($("#txtNewPassword").val(), customer_username);*/
alert("OK!")
}
else {
alert("FAIL2");
}
}
//Validation
$("#ChangeAddressForm").validate({
rules: {
txtNewPostalCode: {
required: true,
minlength: 6,
digits: true
},
txtNewCity: {
digits: false
},
txtNewAddress: {
required: true,
alphanumeric: true
}
},
messages: {
txtNewAddress: {
required: "Address is required",
},
txtNewCity: {
required: "City is required",
digit: "Include only letters!",
},
txtNewPostalCode: {
required: "Postal Code is required!",
minlength: "Postal Code only contains 6 digits!",
digits: "Postal Code only contains digits!"
}
},
focusInvalid: false,
submitHandler: function () {
return false;
},
errorPlacement: function (error, element) {
error.appendTo(element.parent().parent().after());
},
});
//Save Address Button Function
$("#btnSaveAddress").bind("click", function () {
if ($("#ChangeAddressForm").valid()) {
changeAddress();
changeCity();
changePostalCode();
}
});
})();
我希望当3个字段中的文本框发生更改时,输出将启用submit按钮。如果没有更改,则如果存在相同的文本,则按钮将被禁用。您可以在每次输入更改时调用一个函数,然后检查是否输入了所有输入 例如:
<input id = "input1" onchange ="checkIfAllInputsEntered()"/>
<input id = "input2" onchange ="checkIfAllInputsEntered()"/>
<input id = "input3" onchange ="checkIfAllInputsEntered()"/>
Onchange通常只在输入更改焦点时触发一次。 所以您需要使用onkeyup事件。 但您也可以添加onchange和onkeydown以防万一。 我假设您正在使用jQuery。 下面是一个例子:
var old1;
var old2;
var old3;
function checkForChange() {
if (
old1 != $('#in1').val() ||
old2 != $('#in2').val() ||
old3 != $('#in3').val()
) {
$('#save').show();
}
}
$(function() {
old1 = $('#in1').val();
old2 = $('#in2').val();
old3 = $('#in3').val();
});
我试图编写一个函数,它可以检测文本中的变化
字段并启用“保存”按钮
首先,在按钮标签中添加“disabled”属性。然后在按钮中添加一个“onchange”事件。在js中
这样做:
function ontextchanged()
$('#buttonid').prop('disabled',false);
请尝试以下代码:
函数InputChangeListener(){
flag=1;
var firstInput=document.getElementById(“firstInput”);
var secondInput=document.getElementById(“secondInput”);
var thirdInput=document.getElementById(“thirdInput”);
var firstInputVal=document.getElementById(“firstInput”).defaultValue;
var secondInputVal=document.getElementById(“secondInput”).defaultValue;
var thirdInputVal=document.getElementById(“thirdInput”).defaultValue;
var submitButton=document.getElementById(“submitButton”);
if(firstInput.value==firstInputVal | | secondInput.value==secondInputVal | | thirdInput.value==thirdInputVal){
flag=0;
}
如果(标志==1){
submitButton.style.display=“block”;
}否则{
submitButton.style.display=“无”;
}
}
#提交按钮{
显示:无
}
您好,谢谢您的回答,但我找不到输入文本是否为空。但我正在查找包含现有文本的输入字段,如果现有文本发生变化,则启用“保存”按钮,这样您就知道每个输入字段的现有文本了吗?如果您知道所有现有文本,则可以检查值是否为“某个现有文本”,而不是为空或者不是,如果它不是现有的文本,那么翻转flagHi感谢您的回答,非常有用!但我需要在任何一个字段更改时显示该按钮。并非所有3个按钮都需要更改才能显示
function ontextchanged()
$('#buttonid').prop('disabled',false);