Add validators that check if string does not start/end with supplied parameter

baked_in.go

@@ -120,6 +120,8 @@ var (
 		"excludesrune":         excludesRune,
 		"startswith":           startsWith,
 		"endswith":             endsWith,
+		"startsnotwith":        startsNotWith,
+		"endsnotwith":          endsNotWith,
 		"isbn":                 isISBN,
 		"isbn10":               isISBN10,
 		"isbn13":               isISBN13,
@@ -690,6 +692,16 @@ func endsWith(fl FieldLevel) bool {
 	return strings.HasSuffix(fl.Field().String(), fl.Param())
 }
 
+// StartsNotWith is the validation function for validating that the field's value does not start with the text specified within the param.
+func startsNotWith(fl FieldLevel) bool {
+	return !startsWith(fl)
+}
+
+// EndsNotWith is the validation function for validating that the field's value does not end with the text specified within the param.
+func endsNotWith(fl FieldLevel) bool {
+	return !endsWith(fl)
+}
+
 // FieldContains is the validation function for validating if the current field's value contains the field specified by the param's value.
 func fieldContains(fl FieldLevel) bool {
 	field := fl.Field()

doc.go

@@ -814,6 +814,18 @@ This validates that a string value ends with the supplied string value
 
 	Usage: endswith=goodbye
 
+Does Not Start With
+
+This validates that a string value does not start with the supplied string value
+
+	Usage: startsnotwith=hello
+
+Does Not End With
+
+This validates that a string value does not end with the supplied string value
+
+	Usage: endsnotwith=goodbye
+
 International Standard Book Number
 
 This validates that a string value contains a valid isbn10 or isbn13 value.