Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
544 views
in Technique[技术] by (71.8m points)

how to check for the "backspace" character in C

I'd like to know how to check if a user types the "backspace" character.

I'm using the getch() function i.e. "key = getch()" in my C program and i'd like to check when backspace is pressed. the line:

 if(key = '') { ....

doesn't work.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

The problem with reading Backspace is that most terminals are 'cooked' in that keys like backspace are handled by the terminal driver. However, the curses function getch() can read the backspace as it's not tied to the terminal.

Edit

I just noticed your code is using getch() for input. I ran a little test program and getch() returns 127 when you hit backspace. Therefore try:

if (key == 127 || key == 8) { ... /* Checks for both Delete or Backspace */

Also note that your sample code uses the assignment operator = when it should be using the equality operator ==


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...