C++中,变量定义可以在函数中的任意位置,比如函数中任意位置出现的For循环中:
for(int i = 0; i< len; i++) { /*do something;*/ } |
变量i就可以在使用到的地方才给定义;
然而在C语言中,变量的定义一定要在函数体的最开始处;
否则在使用到变量的地方才定义,编译的时候会报不认识此变量,如下这个屏幕字段入口函数:
Fi_120015_01_CICUSENA() GetStr("K_C00101",acRegFlg); /*判断输入的姓名是否为拼音*/ /*取数组长度*/ for(int i = 0; i < len; i++) |
编译,然后就出现下面的错误:
[开发]/usr/AAAAA/src/cds/120015>msoe ->编译 120015.fe ...... 120015.c: "120015.ec", line 248: error: Syntax error before or at: int "120015.ec", line 250: error: undefined symbol: Name "120015.ec", line 253: error: undefined symbol: len "120015.ec", line 253: error: cannot dereference non-pointer type "120015.ec", line 254: error: Syntax error before or at: int "120015.ec", line 254: error: undefined symbol: i "120015.ec", line 254: error: Syntax error before or at: ) "120015.ec", line 260: error: Syntax error before or at: return "120015.ec", line 260: warning: syntax violation: empty declaration 120015.c: "120015.ec", line 248: error: Syntax error before or at: int "120015.ec", line 250: error: undefined symbol: Name "120015.ec", line 253: error: undefined symbol: len "120015.ec", line 253: error: cannot dereference non-pointer type "120015.ec", line 254: error: Syntax error before or at: int "120015.ec", line 254: error: undefined symbol: i "120015.ec", line 254: error: Syntax error before or at: ) "120015.ec", line 260: error: Syntax error before or at: return "120015.ec", line 260: warning: syntax violation: empty declaration *** Error code 2 (bu21) mv: cannot access 120015.so: No such file or directory (error 2) |