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在mysql插入数据表,如果数据中带有'/“会造成语法错误,这个不用解释,你懂的,因此需要写个转义函数,一开始想直接用string的replace,但是这个方法要调用3次
放在服务端感觉效率太低了,于是用C写了个,感觉还可以,时间复杂度跟需要转义字符的个数无关,如果源串没有匹配的话不需要copy操作.
//转义函数,‘转成/'
bool ConverToDBStr( const char* src,char*dst )
{
int i = -1;//记录上次匹配的位置
int dOffset = 0;//目标字符串游标
int nCopy = 0;//本次需要成 copy的字节数
const char*p = src;
while( *p )
{
if( *p=='//'||*p=='/''||*p=='"' )
{
nCopy = p-src-i-1;
memcpy( dst+dOffset,src+i+1,nCopy );
dOffset+=nCopy;
*(dst+Offset)='//';
*(dst+dOffset+1)=*p;
dOffset+=2;
i = p-src;
}
p++;
}
if( dOffset>0 )//有匹配到,copy最后的字符串
{
memcpy( dst+dOffset,src+i+1,p-src-i );
return true;
}
return false;
}
可以看到,这个函数稍微改动下就可以实现replace
作者:ifeng
bitsCN.com
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