我必须在 keydown.backspace 事件的按键上找到从字符串中删除的字符

Question

HTML:

<input mdInput #sampleInput
  (keyup.enter) = "autoAdd(sampleInput)"
  [mdAutocomplete] = "AutocompleteParameter"
  [(ngModel)] = "AutoParameterVal"
placeholder = "Autoparameters..."
  (keyup.enter) = "autoKeyEnter($event.target.value)"
    (keydown.backspace) = "onBackspaceKeydown($event)"
 />

TS:

   onBackspaceKeydown(event) { 
    console.log('event',event)
   }

i have to detect which charecter is deleted from string on press of backspace by using keydown.backspace event .plz help me to sort out this.

Answer 1

使用 selectionStart 检测插入符号的位置

 AutoParameterVal='Sample';
 onBackspaceKeydown($event,ref){
     console.log(ref.selectionStart);
     this.AutoParameterVal[ref.selectionStart-1]
  }

示例：https://stackblitz.com/edit/angular-1oedu4

我必须在 keydown.backspace 事件的按键上找到从字符串中删除的字符

i have to find which charecter deleted from string on keypress of keydown.backspace event

html

javascript

angular2-forms

angular