A dismissible alert its only for allow to close it, if you need display an alert and remember the choice, you need cookies or local storage and some javascript interaction like:
<html>
<head>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.0.0/dist/css/bootstrap.min.css"
integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"
integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.12.9/dist/umd/popper.min.js"
integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.0.0/dist/js/bootstrap.min.js"
integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
crossorigin="anonymous"></script>
</head>
<body>
<div id="wellcome-message"
style="display: none; border: 1px solid black; border-radius: 10px; color: black; background: white; padding: 10px 25px 10px 15px; max-width: 600px;"
class="alert alert-success alert-dismissible"><span
style="font-size: 1em; color: white; background: blue; border-radius: 20px; padding: 8px;" class="close"
data-dismiss="alert" aria-label="close">Dismiss</span>Testing text.</div>
<script>
function IsValidJsonString(Input) {
try {
JSON.parse(Input);
} catch (ex) {
return false;
}
return true;
}
var Base64 = {
_keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
encode: function (input) {
var output = "";
var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
var i = 0;
input = Base64._utf8_encode(input);
while (i < input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output +
this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
}
return output;
},
decode: function (input) {
var output = "";
var chr1, chr2, chr3;
var enc1, enc2, enc3, enc4;
var i = 0;
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
while (i < input.length) {
enc1 = this._keyStr.indexOf(input.charAt(i++));
enc2 = this._keyStr.indexOf(input.charAt(i++));
enc3 = this._keyStr.indexOf(input.charAt(i++));
enc4 = this._keyStr.indexOf(input.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output = output + String.fromCharCode(chr1);
if (enc3 != 64) {
output = output + String.fromCharCode(chr2);
}
if (enc4 != 64) {
output = output + String.fromCharCode(chr3);
}
}
output = Base64._utf8_decode(output);
return output;
},
_utf8_encode: function (string) {
string = string.replace(/\r\n/g, "\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
} else if ((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
} else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
},
_utf8_decode: function (utftext) {
var string = "";
var i = 0;
var c = c1 = c2 = 0;
while (i < utftext.length) {
c = utftext.charCodeAt(i);
if (c < 128) {
string += String.fromCharCode(c);
i++;
} else if ((c > 191) && (c < 224)) {
c2 = utftext.charCodeAt(i + 1);
string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
i += 2;
} else {
c2 = utftext.charCodeAt(i + 1);
c3 = utftext.charCodeAt(i + 2);
string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
i += 3;
}
}
return string;
}
};
setLocalStorage = function (c_name, value, exdays) {
if (value === null || value === undefined) {
window.localStorage.removeItem(c_name);
window.localStorage.removeItem(c_name + "_expire");
} else {
window.localStorage.setItem(c_name, Base64.encode(JSON.stringify(value)));
var exdate = new Date();
exdate.setDate(exdate.getDate() + ($.isNumeric(exdays) ? exdays : 0));
window.localStorage.setItem(c_name + "_expire", Base64.encode(exdate.toUTCString()));
}
};
getLocalStorage = function (c_name) {
var _time = window.localStorage.getItem(c_name + "_expire")
var _value = window.localStorage.getItem(c_name);
try {
if (_time !== null && _time !== undefined) {
if (Date.parse(Base64.decode(_time)) <= new Date()) {
window.localStorage.removeItem(c_name + "_expire");
window.localStorage.removeItem(c_name);
return null;
} else {
if (IsValidJsonString(Base64.decode(_value)))
return JSON.parse(Base64.decode(_value));
}
}
} catch (ex) {
return null;
}
return null;
};
$(function () {
if (!getLocalStorage("WellcomeMessage"))
$("#wellcome-message").show();
$("#wellcome-message span.close").click(function () {
setLocalStorage("WellcomeMessage", true, 999999);
});
});
</script>
</body>
</html>
Tested ;)