function str_replace(search, replace, string) {
	while(string.indexOf(search) != -1) {
		var array = string.split(search);
		string = array.join(replace);
	}
	return string;
}
 
// Example
var str = 'testing\r\nthis';
trace(str);
 
var newString = str;
newString = str_replace("\r", '', newString);
newString = str_replace("\n", ' ', newString);
 
trace(newString);