C\u8bed\u8a00\u7f16\u7a0b\u6280\u5de7 \u5173\u4e8econst\u548c#define\u7684\u533a\u522b\u5fc3\u5f97

\u7b26\u53f7\u53d8\u91cf\u4e0d\u5206\u914d\u5185\u5b58\uff0c\u5e38\u53d8\u91cf\u5206\u914d\u5185\u5b58\u3002
\u4f60\u5b9a\u4e49\u4e00\u4e2a\u7b26\u53f7\u53d8\u91cf\uff1a#Define PI 3.14

\u7136\u540e\u4f60\u7684\u7a0b\u5e8f\u4f8b\u5982\u662f\u8fd9\u6837\u7684\uff1afloat a=PI*PI;\u5b9a\u4e49\u4e86\u4e00\u4e2afloat\u53d8\u91cfa\uff0c\u5176\u503c\u662fPI*PI\u3002\u7136\u540e\u4f60\u7684\u8fd9\u4e2a\u7a0b\u5e8f\u7ecf\u8fc7\u9884\u7f16\u8bd1,\u53d8\u6210\u4e86\uff1afloat a=3.14*3.14;3.14\u539f\u578b\u66ff\u6362\u4e86PI\uff0c\u6240\u4ee5\u4e0d\u9700\u8981\u4e3aPI\u8fd9\u4e2a\u7b26\u53f7\u53d8\u91cf\u5206\u914d\u5185\u5b58\uff0c\u5b9a\u4e49\u7b26\u53f7\u53d8\u91cf\u7684\u610f\u4e49\u53ea\u662f\u5728\u4e8e\u65b9\u4fbf\u7406\u89e3\uff0c\u4f60\u770b\u52303.14\u8fd9\u4e2a\u503c\u4e0d\u4e00\u5b9a\u60f3\u5230\u4ed6\u662f\u5706\u5468\u7387\uff0c\u4f46\u662f\u770b\u5230PI\u4f60\u5c31\u77e5\u9053\u4ed6\u662f3.14.
\u5e38\u53d8\u91cf\u5176\u5b9e\u548c\u666e\u901a\u53d8\u91cf\u4e00\u6837\uff0c\u90fd\u662f\u9700\u8981\u5206\u914d\u5185\u5b58\u7684\uff0c\u4f46\u662f\u5e38\u53d8\u91cf\u7684\u503c\u662f\u4e0d\u80fd\u6539\u53d8\u7684\u3002
\u4e3a\u4ec0\u4e48\u8bf4\u5e38\u53d8\u91cf\u4f18\u4e8e\u7b26\u53f7\u53d8\u91cf\uff0c\u56e0\u4e3a\u5e38\u53d8\u91cf\u5b89\u5168\uff1a
\u4f8b\u5982\uff1a\u4f60\u5b9a\u4e49\u4e00\u4e2a\u7b26\u53f7\u53d8\u91cf#Define PI 3.14+3.14
\u7136\u540e\u4f60\u7684\u7a0b\u5e8f\u4f8b\u5982\u662f\u8fd9\u6837\u7684\uff1afloat a=PI*PI;\u5b9a\u4e49\u4e86\u4e00\u4e2afloat\u53d8\u91cfa\uff0c\u5176\u503c\u662fPI*PI\u3002\u7136\u540e\u4f60\u7684\u8fd9\u4e2a\u7a0b\u5e8f\u7ecf\u8fc7\u9884\u7f16\u8bd1,\u53d8\u6210\u4e86\uff1afloat a=3.14+3.14*3.14+3.14; 3.14+3.14\u539f\u578b\u66ff\u6362\u4e86PI\u3002
\u5982\u679c\u4f60\u5b9a\u4e49\u5e38\u53d8\u91cf\uff1aConst float PI=3.14+3.14\uff1b\u5982\u679c\u4f60\u7684\u7a0b\u5e8f\uff1afloat a=PI*PI;\u5b9a\u4e49\u4e86\u4e00\u4e2afloat\u53d8\u91cfa\uff0c\u5176\u503c\u662fPI*PI\u3002\u7136\u540e\u4f60\u7684\u8fd9\u4e2a\u7a0b\u5e8f\u7ecf\u8fc7\u9884\u7f16\u8bd1,\u53d8\u6210\u4e86\uff1afloat a=(3.14+3.14)*(3.14+3.14);
\u6240\u4ee5\u5e38\u53d8\u91cf\u66f4\u5b89\u5168\uff0c\u4e0d\u4f1a\u51fa\u73b0\u4e0a\u9762\u7684\u6b67\u4e49\u3002

const\u4e0edefine\u3002\u4e24\u8005\u90fd\u53ef\u4ee5\u7528\u6765\u5b9a\u4e49\u5e38\u91cf\uff0c\u4f46\u662fconst\u5b9a\u4e49\u65f6\uff0c\u5b9a\u4e49\u4e86\u5e38\u91cf\u7684\u7c7b\u578b\uff0c\u6240\u4ee5\u66f4\u7cbe\u786e\u4e00\u4e9b\u3002#define\u53ea\u662f\u7b80\u5355\u7684\u6587\u672c\u66ff\u6362\uff0c\u9664\u4e86\u53ef\u4ee5\u5b9a\u4e49\u5e38\u91cf\u5916\uff0c\u8fd8\u53ef\u4ee5\u7528\u6765\u5b9a\u4e49\u4e00\u4e9b\u7b80\u5355\u7684\u51fd\u6570\uff0c\u6709\u70b9\u7c7b\u4f3c\u5185\u7f6e\u51fd\u6570\u3002const\u548cdefine\u5b9a\u4e49\u7684\u5e38\u91cf\u53ef\u4ee5\u653e\u5728\u5934\u6587\u4ef6\u91cc\u9762\u3002\uff08\u5c0f\u6ce8\uff1a\u53ef\u4ee5\u591a\u6b21\u58f0\u660e\uff0c\u4f46\u53ea\u80fd\u5b9a\u4e49\u4e00\u6b21\uff09