Question

I need javascript regex that will allow english or hebrew characters but not both mixed.
for example:

• myuser – OK.
• myאבג – NOT OK.
• אבגדה – OK.

Answer 1

Matches strings entirely of the Hebrew unicode range, or entirely alpha/numeric/underscore.

/^(?:[\u0590-\u05FF\uFB1D-\uFB40]+|[\w]+)$/i

Got the Hebrew unicode ranges from wikipedia.

var RE_SINGLE_LANG = /^(?:[\u0590-\u05FF\uFB1D-\uFB40]+|[\w]+)$/i;
if (!RE_SINGLE_LANG.exec(myText)) {
   alert("NOT VALID");
}