c# - Textbox cannot be cleared with button press -


i keep getting error message whenever tried clear textbox2. how can solve this? 

private void textbox2_textchanged(object sender, eventargs e)     {         string hexkey = this.textbox2.text;         if(textbox2.focused)         int key = convert.toint32(hexkey, 16);     }  private void button2_click_1(object sender, eventargs e)     {         textbox2.clear();     }

[error]: system.argumentoutofrangeexception: 'index out of range. must non-negative , less size of collection. parameter name: startindex'

[solution]:

private void textbox2_textchanged(object sender, eventargs e)     {         string hexkey = this.textbox2.text;         if(textbox2.focused) //add line in         int key = convert.toint32(hexkey, 16);     }

firzanah, when clear textbox2, textchanged event trigger. since there won't in text box @ point, error occur when try convert nothing int32. solve problem, add if(textbox2.focused) condition change event or, better yet, check you've got int begin with:

private void textbox2_textchanged(object sender, eventargs e)         {             int n;             bool isnumeric = int.tryparse(textbox2.text, out n);             if (!isnumeric) return;             string hexkey = textbox2.text;             int key = convert.toint32(hexkey, 16);         }

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