From b24f080b2ab1851d446ffb87ca3b31e165757531 Mon Sep 17 00:00:00 2001
From: PM Extra <pm@jubeat.net>
Date: Fri, 18 Dec 2020 18:19:55 +0800
Subject: [PATCH] Fix AbpStringExtensions

For now, `"".RemovePreFix("x")` will return null.
It's not a expected result. I think we shouldn't make empty string be null when trim prefix or postfix.
---
 framework/src/Volo.Abp.Core/System/AbpStringExtensions.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/framework/src/Volo.Abp.Core/System/AbpStringExtensions.cs b/framework/src/Volo.Abp.Core/System/AbpStringExtensions.cs
index 6aa3deb4f0..76ae06a5e0 100644
--- a/framework/src/Volo.Abp.Core/System/AbpStringExtensions.cs
+++ b/framework/src/Volo.Abp.Core/System/AbpStringExtensions.cs
@@ -133,7 +133,7 @@ namespace System
         {
             if (str.IsNullOrEmpty())
             {
-                return null;
+                return str;
             }
 
             if (postFixes.IsNullOrEmpty())
@@ -174,7 +174,7 @@ namespace System
         {
             if (str.IsNullOrEmpty())
             {
-                return null;
+                return str;
             }
 
             if (preFixes.IsNullOrEmpty())