Placeholder not working for Internet Explorer
Placeholder for my textbox in below format is not working for Internet Explorer. Is there anyway to display placeholder for TextBox in Internet Explorer?
<asp:TextBox id="email" runat="server" width="300" placeholder="Your email" />
Is there any simple way just by using any JavaScript. I am not interested to make it complicated using jQuery.
You can imitate this using pure JavaScript:
var _debug = false;
var _placeholderSupport = function() {
var t = document.createElement("input");
t.type = "text";
return (typeof t.placeholder !== "undefined");
}();
window.onload = function() {
var arrInputs = document.getElementsByTagName("input");
var arrTextareas = document.getElementsByTagName("textarea");
var combinedArray = [];
for (var i = 0; i < arrInputs.length; i++)
combinedArray.push(arrInputs[i]);
for (var i = 0; i < arrTextareas.length; i++)
combinedArray.push(arrTextareas[i]);
for (var i = 0; i < combinedArray.length; i++) {
var curInput = combinedArray[i];
if (!curInput.type || curInput.type == "" || curInput.type == "text" || curInput.type == "textarea")
HandlePlaceholder(curInput);
else if (curInput.type == "password")
ReplaceWithText(curInput);
}
if (!_placeholderSupport) {
for (var i = 0; i < document.forms.length; i++) {
var oForm = document.forms[i];
if (oForm.attachEvent) {
oForm.attachEvent("onsubmit", function() {
PlaceholderFormSubmit(oForm);
});
}
else if (oForm.addEventListener)
oForm.addEventListener("submit", function() {
PlaceholderFormSubmit(oForm);
}, false);
}
}
};
function PlaceholderFormSubmit(oForm) {
for (var i = 0; i < oForm.elements.length; i++) {
var curElement = oForm.elements[i];
HandlePlaceholderItemSubmit(curElement);
}
}
function HandlePlaceholderItemSubmit(element) {
if (element.name) {
var curPlaceholder = element.getAttribute("placeholder");
if (curPlaceholder && curPlaceholder.length > 0 && element.value === curPlaceholder) {
element.value = "";
window.setTimeout(function() {
element.value = curPlaceholder;
}, 100);
}
}
}
function ReplaceWithText(oPasswordTextbox) {
if (_placeholderSupport)
return;
var oTextbox = document.createElement("input");
oTextbox.type = "text";
oTextbox.id = oPasswordTextbox.id;
oTextbox.name = oPasswordTextbox.name;
//oTextbox.style = oPasswordTextbox.style;
oTextbox.className = oPasswordTextbox.className;
for (var i = 0; i < oPasswordTextbox.attributes.length; i++) {
var curName = oPasswordTextbox.attributes.item(i).nodeName;
var curValue = oPasswordTextbox.attributes.item(i).nodeValue;
if (curName !== "type" && curName !== "name") {
oTextbox.setAttribute(curName, curValue);
}
}
oTextbox.originalTextbox = oPasswordTextbox;
oPasswordTextbox.parentNode.replaceChild(oTextbox, oPasswordTextbox);
HandlePlaceholder(oTextbox);
if (!_placeholderSupport) {
oPasswordTextbox.onblur = function() {
if (this.dummyTextbox && this.value.length === 0) {
this.parentNode.replaceChild(this.dummyTextbox, this);
}
};
}
}
function HandlePlaceholder(oTextbox) {
if (!_placeholderSupport) {
var curPlaceholder = oTextbox.getAttribute("placeholder");
if (curPlaceholder && curPlaceholder.length > 0) {
Debug("Placeholder found for input box '" + oTextbox.name + "': " + curPlaceholder);
oTextbox.value = curPlaceholder;
oTextbox.setAttribute("old_color", oTextbox.style.color);
oTextbox.style.color = "#c0c0c0";
oTextbox.onfocus = function() {
var _this = this;
if (this.originalTextbox) {
_this = this.originalTextbox;
_this.dummyTextbox = this;
this.parentNode.replaceChild(this.originalTextbox, this);
_this.focus();
}
Debug("input box '" + _this.name + "' focus");
_this.style.color = _this.getAttribute("old_color");
if (_this.value === curPlaceholder)
_this.value = "";
};
oTextbox.onblur = function() {
var _this = this;
Debug("input box '" + _this.name + "' blur");
if (_this.value === "") {
_this.style.color = "#c0c0c0";
_this.value = curPlaceholder;
}
};
}
else {
Debug("input box '" + oTextbox.name + "' does not have placeholder attribute");
}
}
else {
Debug("browser has native support for placeholder");
}
}
function Debug(msg) {
if (typeof _debug !== "undefined" && _debug) {
var oConsole = document.getElementById("Console");
if (!oConsole) {
oConsole = document.createElement("div");
oConsole.id = "Console";
document.body.appendChild(oConsole);
}
oConsole.innerHTML += msg + "<br />";
}
}
This will do nothing if the browser is already supporting the placeholder attribute, and in case it's not supported (eg the browser is IE) it will add very similar functionality - text shown by default that disappear on focus and appears again if user didn't type anything.
Live test case.
Bug Fixes
Nov 6, 2012: Previous code failed to detect when browser didn't have native support for placeholder. Using code found in this other post it's now fixed. Affected browsers: IE7 and IE8, maybe others as well. Also added debug support to help debug future problems.
Jan 30, 2013:
Adding support for password input as well. Since IE8 and below won't allow dynamic change of input type, the code is replacing the password input with text input as long as there is no password typed, thus the placeholder text will be visible.
Fixed bug that caused the placeholder value to be sent where empty value should be sent to the server when the form associated with the input is being submitted. To achieve this, code is attached to the form submit event and clear the value if needed.
Jan 24, 2014: adding support for <textarea> elements.
There are a number of polyfill scripts written that will add placeholder support to browsers that don't natively support the technology.
Rather than repeating what's been written elsewhere, I'd recommend going here: https://github.com/Modernizr/Modernizr/wiki/HTML5-Cross-browser-Polyfills and scroll down about 1/3 of the way to the section entitled Web Forms : input placeholder for a few different options (both native JS and jQuery). Since that entire page is curated by the HTML5 Boilerplate team you can be fairly certain that the scripts provided are of decent quality.
Edit: just saw your comment about not using HTML5. The scripts on the link I provided should still work even if you're not using the HTML5 doctype (no guarantees expressed or implied, etc.).
我写了这个简单的代码，测试时它对我很好：
placeholder=function(){
$('input, textarea').each(function(){
var holder=$(this).attr('placeholder');
if(typeof(holder) !=='undefined'){
$(this).val(holder);
$(this).bind('click',function(){
$(this).val('');
}).blur(function(){
$(this).val(holder);
});
}
});
};
$(document).ready(placeholder);
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