I have been attempting to check that a username exists in a text file using JavaScript. I call the CheckUserExists() method (below) passing in the username. However the readyState is always 1 so the file does not get read.
The webpage I am calling it from is something like this: www.mysite.co.uk/html/home.html
and the text file is located at: www.mysite.co.uk/html/resources/somefile.txt
I know really I should use server-side scripts but this is not possible so I need to use JavaScript.
Anyone got any ideas where I am going wrong? This has been doing my head in all day so hopefully someone knows what I have done wrong.
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- var name;
- var file;
- function CheckUserExists(username)
- {
- name=username;
- if(window.XMLHttpRequest)
- {
- file = new XMLHttpRequest();
- }
- else if(window.ActiveXObject)
- {
- file = new ActiveXObject("Microsoft.XMLHTTP");
- }
- else
- {
- alert("Error XMLHTTP Not Supported");
- }
- file.open("GET", "resources/somefile.txt", true);
- file.onreadystagechange = ReadFile();
- file.send(null);
- }
- function ReadFile()
- {
- if(file.readyState == 4 || file.readyState == "complete") //Check file is ready to parse
- {
- if(file.status == 200) //Check file was found
- {
- //Read file etc...
- }
- }
- else
- {
- alert(file.readyState);
- }
- }