question about correctly structuring javascript, css, and sv

i have a index.html file which includes svg and CSS file and 2 javascripts file and has a javascript function inside of itfor some reason i cannot get the javascript function to run. is the strucutre...

Check if a String is HTML or XML

Is there a way to check if a String is HTML or XML in JavaScript? Preferably using jQuery rather than some other library? Why I need to do this is because I need to know if it possible to have a function...