diff --git a/binding/c/ip2region.c b/binding/c/ip2region.c
index c20d88e..87e0ed0 100644
--- a/binding/c/ip2region.c
+++ b/binding/c/ip2region.c
@@ -35,12 +35,15 @@ IP2R_API uint_t ip2region_create(ip2region_t ip2rObj, char *dbFile)
     if ( ip2rObj->dbHandler == NULL  ) {
         IP2R_FREE(ip2rObj->HeaderSip);
         IP2R_FREE(ip2rObj->HeaderPtr);
+        //fprintf(stderr, "Fail to open the db file %s\n", ip2rObj>dbFile);
+        //exit(-1);
         return 0;
     }
 
     ip2rObj->firstIndexPtr = 0;
     ip2rObj->lastIndexPtr  = 0;
     ip2rObj->totalBlocks   = 0;
+    ip2rObj->dbBinStr      = NULL;
 
     return 1;
 }
@@ -63,9 +66,94 @@ IP2R_API uint_t ip2region_destroy(ip2region_t ip2rObj)
         ip2rObj->dbHandler = NULL;
     }
 
+    //free the db binary string
+    if ( ip2rObj->dbBinStr != NULL ) {
+        IP2R_FREE(ip2rObj->dbBinStr);
+        ip2rObj->dbBinStr = NULL;
+    }
+
     return 1;
 }
 
+/**
+ * get the region associated with the specified ip address with the memory binary search algorithm
+ *
+ * @param   ip2rObj
+ * @param   ip
+ * @param   datablock
+*/
+IP2R_API uint_t ip2region_memory_search(ip2region_t ip2rObj, uint_t ip, datablock_t datablock) 
+{
+    int l, h, m, p;
+    uint_t sip, eip, dptr;
+    int dataLen, dataptr;
+    long filesize;
+    char *buffer;
+
+    if ( ip2rObj->dbBinStr == NULL ) {
+        //get the size of the file
+        fseek(ip2rObj->dbHandler, 0, SEEK_END);
+        filesize = ftell(ip2rObj->dbHandler);
+        fseek(ip2rObj->dbHandler, 0, SEEK_SET);
+
+        //alloc the buffer size
+        ip2rObj->dbBinStr = IP2R_MALLOC(filesize);
+        if ( ip2rObj->dbBinStr == NULL ) {
+            return 0;
+        }
+
+        //now read the whole file
+        if ( fread(ip2rObj->dbBinStr, filesize, 1, ip2rObj->dbHandler) != 1 ) {
+            return 0;
+        }
+
+        buffer = ip2rObj->dbBinStr;
+        ip2rObj->firstIndexPtr = getUnsignedInt(buffer, 0);
+        ip2rObj->lastIndexPtr  = getUnsignedInt(buffer, 4);
+        ip2rObj->totalBlocks   = (ip2rObj->lastIndexPtr-ip2rObj->firstIndexPtr)/INDEX_BLOCK_LENGTH + 1;
+    }
+
+    l = 0; h = ip2rObj->totalBlocks; dptr = 0;
+    while ( l <= h ) {
+        m = (l + h) >> 1;
+        p = ip2rObj->firstIndexPtr + m * INDEX_BLOCK_LENGTH;
+
+        buffer = ip2rObj->dbBinStr + p;
+        sip    = getUnsignedInt(buffer, 0);
+        if ( ip < sip ) {
+            h = m - 1;
+        } else {
+            eip = getUnsignedInt(buffer, 4);
+            if ( ip > eip ) {
+                l = m + 1;
+            } else {
+                dptr = getUnsignedInt(buffer, 8);
+                break;
+            }
+        }
+    }
+
+    if ( dptr == 0 ) return 0;
+
+    //get the data
+    dataLen = ((dptr >> 24) & 0xFF);
+    dataptr = (dptr & 0x00FFFFFF);
+    buffer  = ip2rObj->dbBinStr + dataptr;
+
+    //fill the data to the datablock
+    datablock->city_id = getUnsignedInt(buffer, 0);
+    dataLen -= 4;    //reduce the length of the city_id
+    memcpy(datablock->region, buffer + 4, dataLen); 
+    datablock->region[dataLen] = '\0';
+
+    return 1;
+}
+
+IP2R_API uint_t ip2region_memory_search_string(ip2region_t ip2rObj, char *ip, datablock_t datablock)
+{
+    return ip2region_memory_search(ip2rObj, ip2long(ip), datablock);
+}
+
 /**
  * get the region associated with the specifield ip address with binary search algorithm
  *
diff --git a/binding/c/ip2region.h b/binding/c/ip2region.h
index bf7eac7..33820b3 100644
--- a/binding/c/ip2region.h
+++ b/binding/c/ip2region.h
@@ -52,7 +52,9 @@ typedef struct {
 	uint_t *HeaderSip;		//header start ip blocks
 	uint_t *HeaderPtr;		//header ptr blocks
 	uint_t headerLen;		//header block number
+    char *dbFile;           //path of db file
 	FILE *dbHandler;		//file handler
+    char *dbBinStr;         //db binary string for memory search mode
 
 	uint_t firstIndexPtr;	//first index ptr
 	uint_t lastIndexPtr;	//last index ptr
@@ -79,14 +81,26 @@ typedef datablock_entry * datablock_t;
 IP2R_API uint_t ip2region_create(ip2region_t, char *);
 
 /**
- * destroy the specifield ip2region object
+ * destroy the specified ip2region object
  *
  * @param	ip2region_t
 */
 IP2R_API uint_t ip2region_destroy(ip2region_t);
 
 /**
- * get the region associated with the specifield ip address with binary search algorithm
+ * get the region associated with the specified ip address with the memory binary search algorithm
+ *
+ * @param   ip2region_t
+ * @param   uint_t
+ * @param   datablock_t
+ * @date    2016/06/30
+*/
+IP2R_API uint_t ip2region_memory_search(ip2region_t, uint_t, datablock_t);
+IP2R_API uint_t ip2region_memory_search_string(ip2region_t, char *, datablock_t);
+
+
+/**
+ * get the region associated with the specified ip address with binary search algorithm
  *
  * @param	ip2rObj
  * @param	ip
@@ -97,7 +111,7 @@ IP2R_API uint_t ip2region_binary_search(ip2region_t, uint_t, datablock_t);
 IP2R_API uint_t ip2region_binary_search_string(ip2region_t, char *, datablock_t);
 
 /**
- * get the region associated with the specifield ip address with b-tree algorithm
+ * get the region associated with the specified ip address with b-tree algorithm
  *
  * @param	ip2rObj
  * @param	ip
@@ -108,7 +122,7 @@ IP2R_API uint_t ip2region_btree_search(ip2region_t, uint_t, datablock_t);
 IP2R_API uint_t ip2region_btree_search_string(ip2region_t, char *, datablock_t);
 
 /**
- * get a unsinged long(4bytes) from a specifield buffer start from the specifield offset
+ * get a unsinged long(4bytes) from a specified buffer start from the specified offset
  *
  * @param	buffer
  * @param	offset
diff --git a/binding/c/testSearcher.c b/binding/c/testSearcher.c
index d5d8e32..a7661a7 100644
--- a/binding/c/testSearcher.c
+++ b/binding/c/testSearcher.c
@@ -54,22 +54,27 @@ int main( int argc, char **argv )
     memset(&datablock, 0x00, sizeof(datablock_entry));
 
     if ( argc < 2  ) {
-        printf("Usage: a.out [ip2region db file path] [algorithm]");
+        printf("Usage: a.out [ip2region db file path] [algorithm]\n");
         return 0;
     }
 
     dbFile      = argv[1];
     algorithm = "B-tree";
     func_ptr  = ip2region_btree_search_string;
-    if ( argc >= 3 && strcmp(argv[2], "binary") == 0 ) {
-        algorithm = "Binary";
-        func_ptr = ip2region_binary_search_string;
+    if ( argc >= 3 ) {
+        if ( strcmp(argv[2], "binary") == 0 ) {
+            algorithm = "Binary";
+            func_ptr = ip2region_binary_search_string;
+        } else if ( strcmp(argv[2], "memory") == 0 ) {
+            algorithm = "Memory";
+            func_ptr = ip2region_memory_search_string;
+        }
     }
 
     //create a new ip2rObj
     printf("+--initializing %s ... \n", algorithm);
     if ( ip2region_create(&ip2rEntry, dbFile) == 0 ) {
-        println("Error: Fail to create the ip2region object");
+        println("Error: Fail to create the ip2region object\n");
         return 0;
     }