diff --git a/XMLDictionary/XMLDictionary.h b/XMLDictionary/XMLDictionary.h
index 3f51968..344c184 100644
--- a/XMLDictionary/XMLDictionary.h
+++ b/XMLDictionary/XMLDictionary.h
@@ -106,6 +106,8 @@ static NSString *const XMLDictionaryAttributePrefix = @"_";
 
 - (NSString *)XMLEncodedString;
 
+- (NSString *)filterXMLSpecial;
+
 @end
 
 
diff --git a/XMLDictionary/XMLDictionary.m b/XMLDictionary/XMLDictionary.m
index a7f7ab0..e4a5f39 100644
--- a/XMLDictionary/XMLDictionary.m
+++ b/XMLDictionary/XMLDictionary.m
@@ -557,4 +557,37 @@ - (NSString *)XMLEncodedString
             stringByReplacingOccurrencesOfString:@"\'" withString:@"'"];
 }
 
+- (NSString *)filterXMLSpecial
+{
+    NSData *myD = [self dataUsingEncoding:NSUTF8StringEncoding];
+    Byte *bytes = (Byte *)[myD bytes];
+    NSString *hexStr = @"";
+    for(NSUInteger i = 0; i < [myD length]; i++)
+    {
+        @autoreleasepool
+        {
+            // xml无效字符
+            unsigned int anHex = bytes[i]&0xff;
+            if((anHex > 0x00 && anHex <= 0x08) ||
+               (anHex >= 0x0b && anHex <= 0x0c) ||
+               (anHex >= 0x0e && anHex <= 0x1f))
+            {
+                continue;
+            }
+            
+            NSString *newHexStr = [NSString stringWithFormat:@"%x",bytes[i]&0xff];///16进制数
+            
+            if([newHexStr length]==1)
+            {
+                hexStr = [NSString stringWithFormat:@"%@0%@",hexStr, newHexStr];
+            }
+            else
+            {
+                hexStr = [NSString stringWithFormat:@"%@%@",hexStr, newHexStr];
+            }
+        }
+    }
+    return hexStr;
+}
+
 @end