diff --git a/lib/server/rest.js b/lib/server/rest.js
index 9a92406e..18557ddd 100644
--- a/lib/server/rest.js
+++ b/lib/server/rest.js
@@ -99,8 +99,8 @@
      */
     function sendData(params, callback) {
         var p       = params,
-            isFS    = Util.isContainStrAtBegin(p.name, CloudFunc.FS),
-            isMD    = Util.isContainStrAtBegin(p.name, '/markdown');
+            isFS    = /^\/fs/.test(p.name),
+            isMD    = /^\/markdown/.test(p.name);
         
         if (isFS)
             onFS(params, callback);
diff --git a/lib/server/route.js b/lib/server/route.js
index f7a1c164..a6eabd98 100644
--- a/lib/server/route.js
+++ b/lib/server/route.js
@@ -120,7 +120,7 @@
         
         name    = ponse.getPathName(request);
         isAuth  = Util.strCmp(name, ['/auth', '/auth/github']);
-        isFS    = Util.strCmp(name, '/') || Util.isContainStrAtBegin(name, FS);
+        isFS    = RegExp('^/$|' + FS).test(name);
         
         p       = {
             request     : request,
diff --git a/lib/util.js b/lib/util.js
index bcfe8ada..bbd7557b 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -269,36 +269,6 @@
             return is;
         };
         
-        /**
-         * is pStr1 contains pStr2 at begin
-         * @param pStr1
-         * @param pStr2
-         */
-        this.isContainStrAtBegin    = function(pStr1, pStr2) {
-            var i, n, length, subStr, ret,
-                isStr1  = Util.type.string(pStr1),
-                isArr2  = Util.type.array(pStr2);
-            
-            if (isStr1)
-                 if (isArr2) {
-                     n = pStr2.length;
-                     
-                     for(i = 0; i < n; i++) {
-                        ret = Util.isContainStrAtBegin(pStr1, pStr2[i]);
-                        
-                        if (ret)
-                            break;
-                     }
-                 } else {
-                    length = pStr2.length,
-                    subStr = pStr1.substring(0, length);
-                    
-                    ret = subStr === pStr2;
-                }
-                
-            return ret;
-        };
-        
         /**
          * function log pArg if it's not empty
          * @param pArg