how to use regular expression in javascript

Question

var pattern=/[A-za-z0-9]/;
if((fs.value||ls.value||ad1.value||ad2.value||pc.value||city.value||email.value)!=pattern)
{alert("fields not entered");
return false;}
else
return true;

Even after entering all the fields in the form, I get alert message "field not entered. Here fs,ls,ad1,ad2,email,pc and city are form field values

Answer 1

You need to take the values from those fields and run them thru the regex matching tool while passing the regex to that method.

var pattern=/[A-za-z0-9]/;
"string to check against regex pattern".match(pattern);

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