How to create HTML page by code [duplicate] - c#

How would I open a new window in JavaScript and insert HTML data instead of just linking to an HTML file?

I would not recomend you to use document.write as others suggest, because if you will open such window twice your HTML will be duplicated 2 times (or more).
Use innerHTML instead
var win = window.open("", "Title", "toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=yes,resizable=yes,width=780,height=200,top="+(screen.height-400)+",left="+(screen.width-840));
win.document.body.innerHTML = "HTML";

You can use window.open to open a new window/tab(according to browser setting) in javascript.
By using document.write you can write HTML content to the opened window.

When you create a new window using open, it returns a reference to the new window, you can use that reference to write to the newly opened window via its document object.
Here is an example:
var newWin = open('url','windowName','height=300,width=300');
newWin.document.write('html to write...');

Here's how to do it with an HTML Blob, so that you have control over the entire HTML document:
https://codepen.io/trusktr/pen/mdeQbKG?editors=0010
This is the code, but StackOverflow blocks the window from being opened (see the codepen example instead):
const winHtml = `<!DOCTYPE html>
<html>
<head>
<title>Window with Blob</title>
</head>
<body>
<h1>Hello from the new window!</h1>
</body>
</html>`;
const winUrl = URL.createObjectURL(
new Blob([winHtml], { type: "text/html" })
);
const win = window.open(
winUrl,
"win",
`width=800,height=400,screenX=200,screenY=200`
);

You can open a new popup window by following code:
var myWindow = window.open("", "newWindow", "width=500,height=700");
//window.open('url','name','specs');
Afterwards, you can add HTML using both myWindow.document.write(); or myWindow.document.body.innerHTML = "HTML";
What I will recommend is that first you create a new html file with any name.
In this example I am using
newFile.html
And make sure to add all content in that file such as bootstrap cdn or jquery, means all the links and scripts. Then make a div with some id or use your body and give that a id. in this example I have given id="mainBody" to my newFile.html <body> tag
<body id="mainBody">
Then open this file using
<script>
var myWindow = window.open("newFile.html", "newWindow", "width=500,height=700");
</script>
And add whatever you want to add in your body tag. using following code
<script>
var myWindow = window.open("newFile.html","newWindow","width=500,height=700");
myWindow.onload = function(){
let content = "<button class='btn btn-primary' onclick='window.print();'>Confirm</button>";
myWindow.document.getElementById('mainBody').innerHTML = content;
}
myWindow.window.close();
</script>
it is as simple as that.

You can also create an "example.html" page which has your desired html and give that page's url as parameter to window.open
var url = '/example.html';
var myWindow = window.open(url, "", "width=800,height=600");

Use this one. It worked for me very perfect.
For New window:
new_window = window.open(URL.createObjectURL(new Blob([HTML_CONTENT], { type: "text/html" })))
for pop-up
new_window = window.open(URL.createObjectURL(new Blob([HTML_CONTENT], { type: "text/html" })),"width=800,height=600")
Replace HTML_CONTENT with your own HTML Code
Like:
new_window = window.open(URL.createObjectURL(new Blob(["<h1>Hello</h1>"], { type: "text/html" })))

if your window.open() & innerHTML works fine, ignore this answer.
following answer only focus on cross-origin access exception
#key-in_short,workaround:: [for cross-origin access exception]
when you exec code in main.html -- which tries to access file window_ImageGallery.html by using window.open() & innerHTML
for anyone who encounter cross-origin access exception
and you dont want to disable/mess_around_with Chrome security policy
-> you may use query string to transfer the html code data, as a workaround.
#details::
#problem-given_situation,#problem-arise_problem::
say you exec following simple window.open command as other answer suggested.
let window_Test = window.open('window_ImageGallery.html', 'Image Enlarged Window' + $(this).attr('src'), 'width=1000,height=800,top=50,left=50');
window_Test.document.body.innerHTML = 'aaaaaa';
you may encounter following cross-origin access exception
window_Test.document.body.innerHTML = 'aaaaaa'; // < Exception here
Uncaught DOMException: Blocked a frame with origin "null" from accessing a cross-origin frame.
=> #problem-solution-workaround::
you may use query string to transfer the html code data, as a workaround. <- Transfer data from one HTML file to another
#eg::
in your main.html
// #>> open ViewerJs in a new html window
eleJq_Img.click(function() {
// #>>> send some query string data -- a list of <img> tags, to the new html window
// #repeat: must use Query String to pass html code data, else you get `Uncaught DOMException: Blocked a frame with origin "null" from accessing a cross-origin frame.` (cross origin access issue)
let id_ThisImg = this.id;
let ind_ThisImg = this.getAttribute('data-index-img');
let url_file_html_window_ImageGallery = 'window_ImageGallery.html'
+ '?queryStr_html_ListOfImages=' + encodeURIComponent(html_ListOfImages)
+ '&queryStr_id_ThisImg=' + encodeURIComponent(id_ThisImg)
+ '&queryStr_ind_ThisImg=' + encodeURIComponent(ind_ThisImg);
// #>>> open ViewerJs in a new html window
let window_ImageGallery = window.open(url_file_html_window_ImageGallery, undefined, 'width=1000,height=800,top=50,left=50');
});
in your window_ImageGallery.html
window.onload = function () {
// #>> get parameter from URL
// #repeat: must use Query String to pass html code data, else you get `Uncaught DOMException: Blocked a frame with origin "null" from accessing a cross-origin frame.` (cross origin access issue)
// https://stackoverflow.com/questions/17502071/transfer-data-from-one-html-file-to-another
let data = getParamFromUrl();
let html_ListOfImages = decodeURIComponent(data.queryStr_html_ListOfImages);
let id_ThisImgThatOpenedTheHtmlWindow = decodeURIComponent(data.queryStr_id_ThisImg);
let ind_ThisImgThatOpenedTheHtmlWindow = decodeURIComponent(data.queryStr_ind_ThisImg);
// #>> add the Images to the list
document.getElementById('windowImageGallery_ContainerOfInsertedImages').innerHTML = html_ListOfImages;
// -------- do your stuff with the html code data
};
function getParamFromUrl() {
let url = document.location.href;
let params = url.split('?')[1].split('&');
let data = {};
let tmp;
for (let i = 0, l = params.length; i < l; i++) {
tmp = params[i].split('=');
data[tmp[0]] = tmp[1];
}
return data
}
#minor-note::
(seems) sometimes you may not get the cross-origin access exception
due to, if you modify the html of 'window_ImageGallery.html' in main.html before window_ImageGallery.html is loaded
above statement is based on my test
& another answer -- window.open: is it possible open a new window with modify its DOM
if you want to make sure to see that Exception,
you can try to wait until the opening html window finish loading, then continue execute your code
#eg::
use defer() <- Waiting for child window loading to complete
let window_ImageGallery = window.open('window_ImageGallery.html', undefined, 'width=1000,height=800,top=50,left=50');
window_ImageGallery.addEventListener("unload", function () {
defer(function (){
console.log(window_ImageGallery.document.body); // < Exception here
});
});
function defer (callback) {
var channel = new MessageChannel();
channel.port1.onmessage = function (e) {
callback();
};
channel.port2.postMessage(null);
}
or use sleep() with async What is the JavaScript version of sleep()?
eleJq_Img.click(async function() {
...
let window_Test = window.open( ...
...
await new Promise(r => setTimeout(r, 2000));
console.log(window_Test.document.body.innerHTML); // < Exception here
});
or you get null pointer exception
if you try to access elements in window_ImageGallery.html
#minor-comment::
There are too many similar Posts about the cross-origin issue. And there are some posts about window.open()
Idk which post is the best place to place the answer. And I picked here.

Related

Read iFrame contents in a WPF browser window c#

I have an HTML document with an iFrame, which i am loading in a webbrowser window. My objective is once that iFrame document is loaded, capture the document contents and search for a particular line.
I am not been able to do it so far, any suggestions ?
HTML CODE
<html>
<body>
<iframe id="monitor" src="http://monitor.baseline.com"></iframe>
</body>
</html>
You can add a JavaScript function to the OnLoad event of the iFrame:
document.getElementById('monitor').onload = function() { }
And then follow these solutions to parse your document. But be aware about cross-site-scripting restrictions. If the src of your iFrame is a totally different domain, it probably won't work.
i got it by doing the below
var javascript = #"
var Frame = document.getElementById('monitor');
window.external.iFrameCheck(Frame.contentWindow.document);
";
var doc = (IHTMLDocument2)webBrowser1.Document;
//Once we have the document, execute our JavaScript in it
doc.parentWindow.execScript(javascript);
this would then call the below c# code
[PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
[ComVisible(true)]
public class ComVisibleObjectForScripting
{
public void iFrameCheck(HTMLDocument FrameDoc)
{
//Do what you want here with your FrameDoc
// the innerHTML will give you the content of the iframe
}
}

Embedding Cgi video in site

Hello All I have various web cameras i would like to embed in my site
http://81.137.212.183:4483/GetData.cgi
The problem is at times the cameras go down so i need to check they are active in c# before attempting to render:
<img height="240" width="320" src="http://81.137.212.183:4483/GetData.cgi" />
Please can someone advise how i can check the cgi is active in c# or any other recommendation. If i simple load the cgi and it is down it causes the browser to crash
One recommendation was to use the code below:
The problem with the below approach is the site is forever loading and a fav icon is never shown as can be seen http://www.camsecure.co.uk/
newImage = new Image();
function LoadNewImage() {
var unique = new Date();
document.images.webcam.src = newImage.src;
newImage.src = "http://collectart.dyndns.org:4484/Jpeg/CamImg.jpg?time=" + unique.getTime();
}
function InitialImage() {
var unique = new Date();
newImage.onload = LoadNewImage();
newImage.src = "http://collectart.dyndns.org:4484/Jpeg/CamImg.jpg?time=" + unique.getTime();
document.images.webcam.src = "http://collectart.dyndns.org:4484/Jpeg/CamImg.jpg?time=" + unique.getTime();
document.images.webcam.onload = "";
}
First off, you need to put some security over that first link. It appears the camera settings are public and available to anyone.
If the only problem is the long loading times slowing the rest of the site down, you could load the images in an iframe rather than directly in an image tag -- then the hang is only in the iframe:
<iframe src="http://81.137.212.183:4483/Simple/home.htm?IMG"></iframe>
To check the IP camera is up, you could simply try to get it's host page:
using System.Net.Http;
...
var uri = new Uri("http://81.137.212.183:4483/Simple/index.htm");
var task = new HttpClient().GetAsync(uri);
if (task.Wait(TimeSpan.FromSeconds(1)) && task.Result.IsSuccessStatusCode)
{
// SUCCESS!
}
else
{
// FAILURE... try next camera
}
However, it looks like the image .cgi location can still fail if the camera is available. In that case it would be best to load in an iframe even if you get success.

Invoke JavaScript from C# code behind [duplicate]

This question already has answers here:
Calling JavaScript Function From CodeBehind
(21 answers)
Closed 9 years ago.
I am trying to learn asp.net. Assuming that I have this code:
if (command.ExecuteNonQuery() == 0)
{
// JavaScript like alert("true");
}
else
{
// JavaScript like alert("false");
}
How to I can invoke JavaScript from C# code behind? How to do that by putting that JavaScript in Scripts directory which is created by default in MS Visual Studio?
Here is method I will use from time to time to send a pop message from the code behind. I try to avoid having to do this - but sometimes I need to.
private void LoadClientScriptMessage(string message)
{
StringBuilder script = new StringBuilder();
script.Append(#"<script language='javascript'>");
script.Append(#"alert('" + message + "');");
script.Append(#"</script>");
Page.ClientScript.RegisterStartupScript(this.GetType(), "messageScript", script.ToString());
}
You can use RegisterStartupScript to load a javascript function from CodeBehind.
Please note that javascript will only run at client side when the page is render at client's browser.
Regular Page
Page.ClientScript.RegisterStartupScript(this.GetType(), "myfunc" + UniqueID,
"myJavascriptFunction();", true);
Ajax Page
You need to use ScriptManager if you use ajax.
ScriptManager.RegisterStartupScript(Page, Page.GetType(), "myfunc" + UniqueID,
"myJavascriptFunction();", true);
Usually these "startupscripts" are handy for translations or passing settings to javascript.
Although the solution Mike provided is correct on the .Net side I doubt in a clean (read: no spaghetti code) production environment this is a good practice. It would be better to add .Net variables to a javascript object like so:
// GA example
public static string GetAnalyticsSettingsScript()
{
var settings = new StringBuilder();
var logged = ProjectContext.CurrentUser != null ? "Logged" : "Not Logged";
var account = Configuration.Configuration.GoogleAnalyticsAccount;
// check the required objects since it might not yet exist
settings.AppendLine("Project = window.Project || {};");
settings.AppendLine("Project.analytics = Project.analytics || {};");
settings.AppendLine("Project.analytics.settings = Project.analytics.settings || {};");
settings.AppendFormat("Project.analytics.settings.account = '{0}';", account);
settings.AppendLine();
settings.AppendFormat("Project.analytics.settings.logged = '{0}';", logged);
settings.AppendLine();
return settings.ToString();
}
And then use the common Page.ClientScript.RegisterStartupScript to add it to the HTML.
private void RegisterAnalyticsSettingsScript()
{
string script = GoogleAnalyticsConfiguration.GetAnalyticsSettingsScript();
if (!string.IsNullOrEmpty(script))
{
Page.ClientScript.RegisterStartupScript(GetType(), "AnalyticsSettings", script, true);
}
}
On the JavaScript side it might look like this:
// IIFE
(function($){
// 1. CONFIGURATION
var cfg = {
trackingSetup: {
account: "UA-xxx-1",
allowLinker: true,
domainName: "auto",
siteSpeedSampleRate: 100,
pluginUrl: "//www.google-analytics.com/plugins/ga/inpage_linkid.js"
},
customVariablesSetup: {
usertype: {
slot: 1,
property: "User_type",
value: "Not Logged",
scope: 1
}
}
};
// 2. DOM PROJECT OBJECT
window.Project = window.Project || {};
window.Project.analytics = {
init: function(){
// loading ga.js here with ajax
},
activate: function(){
var proj = this,
account = proj.settings.account || cfg.trackingSetup.account,
logged = proj.settings.logged || cfg.customVariablesSetup.usertype.value;
// override the cfg with settings from .net
cfg.trackingSetup.account = account;
cfg.customVariablesSetup.usertype.value = logged;
// binding events, and more ...
}
};
// 3. INITIALIZE ON LOAD
Project.analytics.init();
// 4. ACTIVATE ONCE THE DOM IS READY
$(function () {
Project.analytics.activate();
});
}(jQuery));
The advantage with this setup is you can load an asynchronous object and override the settings of this object by .Net. Using a configuration object you directly inject javascript into the object and override it when found.
This approach allows me to easily get translation strings, settings, and so on ...
It requires a little bit knowledge of both.
Please note the real power of tis approach lies in the "direct initialization" and "delayed activation". This is necessary as you might not know when (during loading of the page) these object are live. The delay helps overriding the proper objects.
This might be a long shot, but sometimes I need a c# property/value from the server side displaying or manipulated on the client side.
c# code behind page
public string Name {get; set;}
JavaScript on Aspx page
var name = '<%=Name%>';
Populating to client side is generally easier, depending on your issue. Just a thought!

Javascript works on IE but not on Firefox and gives me error as Error: cprofiledetailscollapse is not defined

I use C#.net.
I wrote JavaScript for hide and show expand and collapse div accordingly. It work well in IE but not on Firefox, not even call the JavaScript function and gives me error as Error: ctl00_cpContents_dlSearchList_ctl08_profiledetailscollapse is not defined.
My JavaScript is as follows
function displayDiv(divCompact, divExpand) {
//alert('1');
var str = "ctl00_cpContents_";
var divstyle = new String();
// alert("ibtnShowHide" + ibtnShowHide);
divstyle = divCompact.style.display;
if (divstyle.toLowerCase() == "block" || divstyle == "") {
divCompact.style.display = "none";
divExpand.style.display = "block";
// ibtnShowHide.ImageUrl = "images/expand_img.GIF";
}
else {
// ibtnShowHide.ImageUrl = "images/restore_img.GIF";
divCompact.style.display = "block";
divExpand.style.display = "none";
}
return false;
}
ctl00_cpContents_dlSearchList_ctl08_profiledetailscollapse is an element id generated by ASP.NET. It's a profiledetailscollapse control inside dlSearchList.
JavaScript variable "ctl00_cpContents_dlSearchList_ctl08_profiledetailscollapse" is not
defined. Firefox does not automatically create, for each element with an id, a
variable in the global scope named after that id and containing a reference
to the element.
You might want to consider using jQuery to make sure that your DOM manipulation is cross-browser compatible.

Getting the executed output of an aspx page after a short delay

I have an aspx page which has some javascript code like
<script>
setTimeout("document.write('" + place.address + "');",1);
</script>
As it is clear from the code it will going to write something on the page after a very short delay of 1 ms. I have created an another page to get the page executed by some query string and get its output. The problem is
I can not avoid the delay as simply writing document.write(place.address); will not print anything as it takes a little time to get values so if I set it in setTimeout for delayed output of 1 ms it always return me a value
If I request the output from another page using
System.Net.WebClient wc = new System.Net.WebClient();
System.IO.StreamReader sr = new System.IO.StreamReader(wc.OpenRead("http://localhost:4859/Default.aspx?lat=" + lat + "&lng=" + lng));
string strData = sr.ReadToEnd();
I get the source code of the document instead of the desired output.
I would like to either avoid that delay or else delayed the client request output so that I get a desired value not the source code.
The JS on default.aspx is
<script type="text/javascript">
var geocoder;
var address;
function initialize() {
geocoder = new GClientGeocoder();
var qs=new Querystring();
if(qs.get("lat") && qs.get("lng"))
{
geocoder.getLocations(new GLatLng(qs.get("lat"),qs.get("lng")),showAddress);
}
else
{
document.write("Invalid Access Or Not valid lat long is provided.");
}
}
function getAddress(overlay, latlng) {
if (latlng != null) {
address = latlng;
geocoder.getLocations(latlng, showAddress);
}
}
function showAddress(r) {
place = r.Placemark[0];
setTimeout("document.write('" + place.address + "');",1);
//document.write(place.address);
}
</script>
and the code on requestClient.aspx is as
System.Net.WebClient wc = new System.Net.WebClient();
System.IO.StreamReader sr = new System.IO.StreamReader(wc.OpenRead("http://localhost:4859/Default.aspx?lat=" + lat + "&lng=" + lng));
string strData = sr.ReadToEnd();
I'm not a JavaScript expert, but I believe using document.write after the page has finished loading is a bad thing. You should be creating an html element that your JavaScript can manipulate, once the calculation is complete.
Elaboration
In your page markup, create a placeholder for where you want the address to appear:
<p id="address">Placeholder For Address</p>
In your JavaScript function, update that placeholder:
function showAddress(r) {
place = r.Placemark[0];
setTimeout("document.getElementById('address').innerHTML = '" + place.address + "';",1);
}
string strData = sr.ReadToEnd();
I get the source code of the document instead of the desired output
(Could you give a sample of the output. I don't think I've seen a web scraper work that way so that would help me to be sure. But if not this is a good example web scraper)
Exactly what are you doing with the string "strData" If you are just writing it out, I recommend you putting it in a Server side control (like a literal). If at all possible, I'd recommend you do this server side using .net rather than waiting 1 ms in javascript (which isn't ideal considering the possibility that 1 ms may or may not be an ideal amount of time to wait on a particular user's machine hence: "client side"). In a case like this and I had to do it client side I would use the element.onload event to determine if a page has finished loading.

Categories