added url validation

Author: Codestar

functions/validate.php

@@ -35,6 +35,24 @@ function csf_validate_numeric( $value ) {
   }
 }
 
+/**
+ *
+ * URL validate
+ *
+ * @since 1.0.0
+ * @version 1.0.0
+ *
+ */
+if( ! function_exists( 'csf_validate_url' ) ) {
+  function csf_validate_url( $value ) {
+
+    if( ! filter_var( $value, FILTER_VALIDATE_URL ) ) {
+      return esc_html__( 'Please write a valid url!', 'csf' );
+    }
+
+  }
+}
+
 /**
  *
  * Required validate