自学教程：C++ subString函数代码示例

static void addSubstitution (Alteration *currAlteration, char* proteinSequenceBeforeIndel, char *proteinSequenceAfterIndel, int indelOffset) {  int lengthBefore,lengthAfter;  static Stringa buffer = NULL;  int i;  int diff;  int index;  stringCreateClear (buffer,100);  index = ((currAlteration->relativePosition - 1) / 3);  lengthBefore = strlen (proteinSequenceBeforeIndel);  lengthAfter = strlen (proteinSequenceAfterIndel);  diff = abs (lengthBefore - lengthAfter);  if (lengthBefore < lengthAfter) {    stringPrintf (buffer,"%d_%c->",index + 1,proteinSequenceBeforeIndel[index]);    for (i = 0; i <= diff; i++) {      stringAppendf (buffer,"%c",proteinSequenceAfterIndel[index + i]);    }  }  else if (lengthBefore > lengthAfter) {    stringPrintf (buffer,"%d_",index + 1);    for (i = 0; i <= diff; i++) {      stringAppendf (buffer,"%c",proteinSequenceBeforeIndel[index + i]);    }    stringAppendf (buffer,"->%c",proteinSequenceAfterIndel[index]);  }  else {    stringPrintf (buffer,"%d_%s->",index,subString (proteinSequenceBeforeIndel,index - 1,index + (int)ceil ((double)indelOffset / 3)));    stringAppendf (buffer,"%s",subString (proteinSequenceAfterIndel,index - 1,index + (int)ceil ((double)indelOffset / 3)));  }   currAlteration->substitution = hlr_strdup (string (buffer));}

	List tokenize(char * tokens , char separator , HeapHandler hh){				List list;		int mark1=0;		int i;		char * token;		if(tokens == NULL)			return NULL;		list = buildSringsList(hh);				for(i=0 ; i<(int)strlen(tokens) ; i++){			if(tokens[i] == separator){				token = subString(tokens + mark1 , 0 , i-mark1-1 , hh);				mark1 = i+1;				if(!equalsStrings(trim(token , hh) , "" ))					addNode(list , token , hh);			}		}		if(i==strlen(tokens)){			token = subString(tokens + mark1 ,0, strlen(tokens) - mark1 -1 , hh);			if(!equalsStrings(trimBlankSpaces(token , hh) , "" ))				addNode(list , token,  hh);		}		return (list->size > 0) ? list : NULL;	}

SimpleString SimpleString::subStringFromTill(char startChar, char lastExcludedChar) const{    int beginPos = find(startChar);    if (beginPos < 0) return "";    int endPos = findFrom((size_t)beginPos, lastExcludedChar);    if (endPos == -1) return subString((size_t)beginPos, size());    return subString((size_t)beginPos, (size_t) (endPos - beginPos));}

    bool String::endsWith(const String& search, bool caseSensitive) const    {        if(caseSensitive)        {            return subString(getSize() - search.getSize()) == search;        }        return subString(getSize() - search.getSize()).toUppercase() == search.toUppercase();    }

SimpleString SimpleString::subStringFromTill(char startChar, char lastExcludedChar) const{    size_t beginPos = find(startChar);    if (beginPos == npos) return "";    size_t endPos = findFrom(beginPos, lastExcludedChar);    if (endPos == npos) return subString(beginPos);    return subString(beginPos, endPos - beginPos);}

struct tagInfo readID3V1(char *file){//if (DEBUG==1) putlog("reading ID3V1");	FILE *f;	struct tagInfo ret;	int res, i, c, val;	char *tag;	char *id;	char *tmp;	tag = (char*) malloc(sizeof(char)*129);	ret.artist=NULL;	f=fopen(file,"rb");	if (f==NULL){       hexchat_print(ph,"file not found while trying to read id3v1");       //if (DEBUG==1) putlog("file not found while trying to read id3v1");       return ret;    }	//int offset=getSize(file)-128;	res=fseek(f,-128,SEEK_END);	if (res!=0) {printf("seek failed/n");fclose(f);return ret;}	//long int pos=ftell(f);	//printf("position= %li/n",pos);	for (i=0;i<128;i++) {		c=fgetc(f);		if (c==EOF) {hexchat_printf(ph,"read ID3V1 failed/n");fclose(f);return ret;}		tag[i]=(char)c;	}	fclose(f);	//printf("tag readed: /n");	id=substring(tag,0,3);	//printf("header: %s/n",id);	if (strcmp(id,"TAG")!=0){hexchat_printf(ph,"no id3 v1 found/n");return ret;}	ret.title=subString(tag,3,30,1);	ret.artist=subString(tag,33,30,1);	ret.album=subString(tag,63,30,1);	ret.comment=subString(tag,97,30,1);	tmp=substring(tag,127,1);	//ret.genre=substring(tag,127,1);		val=(int)tmp[0];	if (val<0)val+=256;	//hexchat_printf(ph, "tmp[0]=%i (%i)",val,tmp[0]);	if ((val<148)&&(val>=0))        ret.genre=GENRES[val];//#############changed	else {         ret.genre="unknown";         //hexchat_printf(ph, "tmp[0]=%i (%i)",val,tmp[0]);    }	//hexchat_printf(ph, "tmp: /"%s/" -> %i",tmp,tmp[0]);	//hexchat_printf(ph,"genre /"%s/"",ret.genre);	//if (DEBUG==1) putlog("id3v1 extracted");	return ret;}

int main (void){//	int stringLength(const char string[]);	void subString(const char source[], int start, int count, char result[]);	char result[50];	subString("character", 4, 3, result);	printf("%s/n", result);	subString("two words", 4, 200, result);	printf("%s/n", result);		return 0;}

void ByteArray::trim(){	int i;	int left = 0;	for (i = 0; i < m_stringLength; ++i)	{		if (!isSpace(m_data[i]))		{			left = i;			break;		}	}	int right = m_stringLength;	for (i = m_stringLength-1; i >= 0; --i)	{		if (!isSpace(m_data[i]))		{			right = i + 1;			break;		}	}	int len = right - left;	if (len < m_stringLength)	{		subString(left, len);	}}

 void visitChar( char c ) {     if( m_mode == None ) {         switch( c ) {         case ' ': return;         case '~': m_exclusion = true; return;         case '[': return startNewMode( Tag, ++m_pos );         case '"': return startNewMode( QuotedName, ++m_pos );         default: startNewMode( Name, m_pos ); break;         }     }     if( m_mode == Name ) {         if( c == ',' ) {             addPattern<TestSpec::NamePattern>();             addFilter();         }         else if( c == '[' ) {             if( subString() == "exclude:" )                 m_exclusion = true;             else                 addPattern<TestSpec::NamePattern>();             startNewMode( Tag, ++m_pos );         }     }     else if( m_mode == QuotedName && c == '"' )         addPattern<TestSpec::NamePattern>();     else if( m_mode == Tag && c == ']' )         addPattern<TestSpec::TagPattern>(); }

const str* str::getToken(const char* pSplitter, bool restart){    if(restart || 0 == mpTokenPtr) {        mpTokenPtr = mpStr;    }    str* pTokenStr = 0;    if('/0' != *mpTokenPtr)    {        // Get char* pointer where we see any chars of pSplitter        char* pFindPtr = strpbrk(mpTokenPtr, pSplitter);        int indexOfFindPtr = mpTokenPtr-mpStr;        int tokenLength = 0;        if(0 == pFindPtr)        {            // No chars found, set token to the remaining string:            tokenLength = strlen(mpTokenPtr);            mpTokenPtr = mpStr + getLen();        }        else {            // Length of token is from previous token ptr to the find pointer            tokenLength = (pFindPtr - mpTokenPtr);            // Set next token pointer to the pointer after the pFindPtr            mpTokenPtr = pFindPtr+1;        }        pTokenStr = (str*)&subString(indexOfFindPtr, tokenLength);    }    return pTokenStr;}

int main (int argc, char *argv[]){  Array breakPoints;  BreakPoint *currBP;  int i;  char *breakPointSequence;  if ((Conf = confp_open(getenv("FUSIONSEQ_CONFPATH"))) == NULL)    return EXIT_FAILURE;  bp_init ("-");  breakPoints = bp_getBreakPoints ();  arraySort (breakPoints,(ARRAYORDERF)sortBreakPointsByTargetAndOffset);    for (i = 0; i < arrayMax (breakPoints); i++) {    currBP = arrp (breakPoints,i,BreakPoint);    breakPointSequence = getBreakPointSequence (currBP->tileCoordinate1,currBP->tileCoordinate2);    printf( ">%s|%s/n%s/n", currBP->tileCoordinate1, currBP->tileCoordinate2, breakPointSequence);    warn(">%s|%s/n%s", 	 currBP->tileCoordinate1, 	 currBP->tileCoordinate2, 	 subString(breakPointSequence, 10, strlen(breakPointSequence)-10));  }  bp_deInit();  confp_close(Conf);  return EXIT_SUCCESS;}

quint64 WebSettings::stringToBytes(const QString &srcString){    quint64 bytes = 1;    QString subString(srcString);    if (srcString.contains(QChar('k'), Qt::CaseInsensitive)             || srcString.contains(QChar('m'), Qt::CaseInsensitive)             || srcString.contains(QChar('g'), Qt::CaseInsensitive)) {        bytes = 1024;        int pos = srcString.indexOf(QChar('k'), 0, Qt::CaseInsensitive);        if (pos == -1) {            bytes *= 1024;            pos = srcString.indexOf(QChar('m'), 0, Qt::CaseInsensitive);            if (pos == -1) {                bytes *= 1024;                pos = srcString.indexOf(QChar('g'), 0, Qt::CaseInsensitive);            }        }        if (pos != -1)            subString = srcString.left(pos);    }    return subString.toDouble() * bytes;}

int String::startsWith(const char* szBegin) const{  if (szStr_ == 0) { return 0; }  String sPrefix = subString(0, UTF8_CharLen(szBegin));  if (sPrefix.empty()) { return 0; }  return sPrefix == szBegin;}

int main(){	char *sub = subString("I love C !", 2,4);	printf("%s", sub);		return 0;}

	char * getValue(char * line , HeapHandler h){		char * formated = trim(line , h);		int indexEqual = indexOfChar(formated , '=');		if(indexEqual > 0)			return subString(formated , indexEqual +1 , (int) strlen(formated)-1 , h);		else			return NULL;	}

	char * getKey(char * line , HeapHandler h){		char * formated = trim(line , h);		int indexEqual = indexOfChar(formated , '=');		if(indexEqual > 0){			return subString(formated , 0 , indexEqual -1 , h);		}else{			return NULL;		}	}

    bool String::startsWith(const String& search, bool caseSensitive) const    {        if(caseSensitive)        {            return find(search) == 0;        }        return subString(0, search.getSize()).toUppercase() == search.toUppercase();    }

// Calls function: subString(int fromIndex, int charCount)const str& str::subString(char fromFirstChar, char toLastChar){    const char fi[] = {fromFirstChar, 0x00};    const char li[] = {toLastChar, 0x00};    const int firstIndex = firstIndexOf(fi);    const int lastIndex  =  lastIndexOf(li);    return subString(firstIndex, lastIndex - firstIndex + 1);}

	char * decodePort(char * m , HeapHandler h){		char * encodedPort , * q , * r;		int i, found = 0;				for(i=0; m[i] != '/0' ; i++){			if(m[i] == ','){				found++;				if(found == 4){					i++;					break;				}			}		}		encodedPort = subString(m , i , strlen(m) , h);		q = subString(encodedPort , 0 , indexOfString(encodedPort , ",")-1 , h);		r = subString(encodedPort , indexOfString(encodedPort , ",")+1 , strlen(encodedPort) , h);				return intToString(atoi(q)*256 + atoi(r) , h);			}

void LanguageString::test() {    // for each string lenght maps the number of strings tested    QMap<int, int> triesMap;    // for each string length maps the number of correct test    QMap<int, int> correctMap;    // the following length variable indicates the length in words    for (int length = text.length() / 3; length > 0; --length) {        for (int i = 0; i < text.length(); ++i) {            QString substr = subString(length, i);            if (substr.length() < 3) continue;            QList<QPair<Language,double> > guessedLanguages =                    languageGuesser()->identify(substr);            triesMap[substr.size()] += 1;            if (!guessedLanguages.empty()) {                correctMap[substr.size()] +=                        Language(guessedLanguages.first().first) == language;            }       }    }    //QTextStream cin(stdin);    QTextStream cout(stdout);    cout << "Testing language " << language << "/n";    //int max = triesMap.keys().last();    int max = 71;    int tries = 0;    int correct = 0;    int startingFrom = 3;    for (int i = 3; i <= max; ++i) {        tries += triesMap.value(i);        correct += correctMap.value(i);        if ((i-2)%3 == 0 || i == max) {            // every 3 iterations and at last iteration            cout << startingFrom << "-" << i << ": " << correct << "/"                 << tries << "(" << double(correct) / tries * 100 << "%)/n";            startingFrom = i+1;            tries = 0;            correct = 0;        }    }//    foreach (int size, triesMap.keys()) {//        int tries = triesMap.value(size);//        int correct = correctMap.value(size);//        cout << size << ": " << correct << "/" << tries << "("//             << double(correct) / tries * 100 << "%)/n";//    }    cout << endl;}

int main(){	char* test_null = NULL;	char test[] = "abcdef";	char test2[] = "xabcdef";	printf( "%s/n", test);		printf( "%i/n", lengthString( test ));		printf( "%i/n", lengthString( test_null ));		printf( "%s/n", appendStringToString( test, test2 ));		char*  connec = appendStringToString( test, test2 );	printf( "%i/n", lengthString( connec ));		printf( "%s/n", subString( test, 2, 4 ));		printf( "%s/n", subString( test, 6, 2 ));		printf( "%s/n", subString( test, 4, 4 ));		printf( "%s/n", subString( test, 1, lengthString( test )));		printf( "%s/n", subString( test, lengthString( test ), 1 ));		printf( "%s/n", invertString( invertString ( test )));		printf( "%s/n", invertString( test ));		 }

	char * trim(char * string , HeapHandler h){		int start = 0;		int end = strlen(string) -1;		while(string[start] == ' ')			start++;		while(string[end] == ' ' || string[end] == '/n' || string[end] == '/0')			end--;		return subString(string , start , end , h);	}

	char * decodeHost(char * m , HeapHandler h){						int i, found = 0;		for(i=0 ; m[i] != '/0' ; i++){			if(m[i] == ','){				found++;				if(found == 4)					break;			}		}				return subString(m , 0 , i-1 , h);	}

	char * trimNewLine(char * string , HeapHandler h){		int start = 0;		int end = (int)strlen(string) -1;		if (end <= start) return string;		while(string[start] == ' ')			start++;		while(string[end] == '/n')			end--;		return subString(string , start , end , h);	}

Vector<String> String::split(const String & s)const{	Vector<String> res;	size_t pos=0;	while(pos < size())	{		size_t fpos=findFirst(pos, s);		if(fpos==SIZE_MAX)			fpos=size();		res.pushBack(subString(pos,fpos - pos));		pos=fpos+s.size();	}	return std::move(res);}

//shortestString: find the shortest string after concatenation.int shortestString(char *str1, char *str2) {    printf("Called /"shortestString/"/n");    char *first=str1+strlen(str1)-1,*second=str2;    int len=strlen(str2),flag=0,i=0;    printf("length of second string is %d and value of first is %s/n",len,first);    if(!strcmp(str1,str2)) {        return 1;        printf("equals and the result is %s/n",str1);    }    else {        if(subString(str1,str2)) {            return 1;            printf("%s is subset of %s/n",str2,str1);        }        else {            for(i=1; i<len; i++) {                printf("inside for loop for %d time/n",i);                printf("strcmp value %d /n",strncmp(str2,first,i));                if(strncmp(str2,first,i)==0) {                    flag=1;                    --first;                    printf("after %d pass first value is %s/n",i,first);                    continue;                }                else {                    --first;                }                if(flag==1) {                    first=str1+strlen(str1)-(i);                    *++first='/0';                    strcat(first,str2);                    printf("first value after concat %s/n",first);                    return 1;                    //break;                }                //printf("out for loop for %d time/n",i);            }            //printf("concatenated string is %s/n",str1);        }    }    printf("return from  /"shortestString/"/n");    return 0;}

//readFile, ghi vao mang l[] voi size la so sv truoc khi them	void readFile(string _file, Student l[], int &size){		ifstream fin;		fin.open(_file.c_str());		if(!fin.is_open())	    {	        cout<<"Khong the mo file./n";	        exit(1);	    }else{	    	string s = "";	    		    	while (getline(fin, s)){				subString(s, l, size);			}			fin.close();	    }		}

std::string getHostByName(const std::string & name, unsigned short port){    auto ret = subString(name, "https://", false).second;    ret = subString(ret, "http://", false).second;    ret += "/";    ret = subString(ret, "/", true).first;    if (std::find_if(ret.begin(), ret.end(), [](char ch) {return !isdigit(ch) && ch != '.'; }) == ret.end())    {        return ret; //ipv4     }    if (std::find_if(ret.begin(), ret.end(), [](char ch) {return !isxdigit(ch) && ch != ':'; }) == ret.end())    {        return ret; //ipv6     }    struct addrinfo *res = nullptr;    struct addrinfo hints;    memset(&hints, 0, sizeof(hints));    hints.ai_family = AF_UNSPEC;    hints.ai_socktype = SOCK_STREAM;    hints.ai_flags = AI_PASSIVE;    if (getaddrinfo(ret.c_str(), toString(port).c_str(), &hints, &res) == 0)    {        char buf[100] = { 0 };        if (res->ai_family == AF_INET)        {            inet_ntop(res->ai_family, &(((sockaddr_in*)res->ai_addr)->sin_addr), buf, 100);        }        else if (res->ai_family == AF_INET6)        {            inet_ntop(res->ai_family, &(((sockaddr_in6*)res->ai_addr)->sin6_addr), buf, 100);        }        return buf;    }    return "";}

 void addPattern() {     std::string token = subString();     if( startsWith( token, "exclude:" ) ) {         m_exclusion = true;         token = token.substr( 8 );     }     if( !token.empty() ) {         Ptr<TestSpec::Pattern> pattern = new T( token );         if( m_exclusion )             pattern = new TestSpec::ExcludedPattern( pattern );         m_currentFilter.m_patterns.push_back( pattern );     }     m_exclusion = false;     m_mode = None; }

//readFile, ghi vao mang l[] voi size la so gv truoc khi them	void LecturerList::readFile(string _file){		ifstream fin;		fin.open(_file.c_str());		if(!fin.is_open())	    {	        cout<<"Khong the mo file./n";	        exit(1);	    }else{	    	string s = "";	    	while (getline(fin, s)){				subString(s);			}			fin.close();	    }		}