how to compare xmlhttp.responsetext?

问题

my code-

document.getElementById("lblmsg").innerHTML=xmlhttp.responseText;
                if(xmlhttp.responseText == 'Available') 
                    {
                         document.getElementById("newid").value = "";
                    }       

although response text is Available but still it is not going inside if condition???

回答1:

Well, that should work.

Are you sure that the response text is exactly Available? Try trimming the response like this:

if(xmlhttp.responseText.trim() == 'Available')

Do you have access to firebug? Try a console.log(xmlhttp) to find out the exact value of the responseText.

回答2:

After hours of searching I found this pitfall: http://www.vertstudios.com/blog/avoiding-ajax-newline-pitfall/

This solved everything without $.trim(). Somewhere in my included files was a lonely linebreak!

来源：https://stackoverflow.com/questions/3449316/how-to-compare-xmlhttp-responsetext