Add option to delay backspace presses on Windows. See #246

native/libwinbridge/bridge.cpp

@@ -495,8 +495,12 @@ void send_string(const wchar_t * string) {
 /*
  * Send the backspace keypress, *count* times.
  */
-void delete_string(int32_t count) {
+void delete_string(int32_t count, int32_t delay) {
-    send_multi_vkey(VK_BACK, count);
+    if (delay != 0) {
+        send_multi_vkey_with_delay(VK_BACK, count, delay);
+    }else{
+        send_multi_vkey(VK_BACK, count);
+    }
 }
 
 void send_vkey(int32_t vk) {
@@ -539,6 +543,27 @@ void send_multi_vkey(int32_t vk, int32_t count) {
     SendInput(vec.size(), vec.data(), sizeof(INPUT));
 }
 
+void send_multi_vkey_with_delay(int32_t vk, int32_t count, int32_t delay) {
+    for (int i = 0; i < count; i++) {
+        INPUT input = { 0 };
+
+        input.type = INPUT_KEYBOARD;
+        input.ki.wScan = 0;
+        input.ki.time = 0;
+        input.ki.dwExtraInfo = 0;
+        input.ki.wVk = vk;
+        input.ki.dwFlags = 0; // 0 for key press
+        SendInput(1, &input, sizeof(INPUT));
+
+        Sleep(delay);
+
+        input.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
+        SendInput(1, &input, sizeof(INPUT));
+
+        Sleep(delay);
+    }
+}
+
 void trigger_paste() {
     std::vector<INPUT> vec;
 

native/libwinbridge/bridge.h

@@ -72,10 +72,15 @@ extern "C" void send_vkey(int32_t vk);
  */
 extern "C" void send_multi_vkey(int32_t vk, int32_t count);
 
+/*
+ * Send the given Virtual Key press multiple times adding a delay between each keypress
+ */
+extern "C" void send_multi_vkey_with_delay(int32_t vk, int32_t count, int32_t delay);
+
 /*
  * Send the backspace keypress, *count* times.
  */
-extern "C" void delete_string(int32_t count);
+extern "C" void delete_string(int32_t count, int32_t delay);
 
 /*
  * Send the Paste keyboard shortcut (CTRL+V)

src/bridge/windows.rs

@@ -57,7 +57,7 @@ extern {
     pub fn send_string(string: *const u16);
     pub fn send_vkey(vk: i32);
     pub fn send_multi_vkey(vk: i32, count: i32);
-    pub fn delete_string(count: i32);
+    pub fn delete_string(count: i32, delay: i32);
     pub fn trigger_paste();
     pub fn trigger_copy();
 }

src/config/mod.rs

@@ -62,6 +62,7 @@ fn default_passive_key() -> KeyModifier { KeyModifier::OFF }
 fn default_enable_passive() -> bool { false }
 fn default_enable_active() -> bool { true }
 fn default_backspace_limit() -> i32 { 3 }
+fn default_backspace_delay() -> i32 { 0 }
 fn default_restore_clipboard_delay() -> i32 { 300 }
 fn default_exclude_default_entries() -> bool {false}
 fn default_secure_input_watcher_enabled() -> bool {true}
@@ -168,6 +169,9 @@ pub struct Configs {
     #[serde(default = "default_fast_inject")]
     pub fast_inject: bool,
 
+    #[serde(default = "default_backspace_delay")]
+    pub backspace_delay: i32,
+
     #[serde(default = "default_matches")]
     pub matches: Vec<Match>,
 

src/keyboard/windows.rs

@@ -62,9 +62,9 @@ impl super::KeyboardManager for WindowsKeyboardManager {
         }
     }
 
-    fn delete_string(&self, _: &Configs, count: i32) {
+    fn delete_string(&self, config: &Configs, count: i32) {
         unsafe {
-            delete_string(count)
+            delete_string(count, config.backspace_delay)
         }
     }