std::strtoimax, std::strtoumax

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NULL結尾的位元組串

功能

字元操作

（C++11）

轉換為數字格式

strtof
strtod
strtold

字元串操作

字元串檢查

內存操作

雜項

Defined in header `<cinttypes>`

std::intmax_t strtoimax(const char* nptr, char** endptr, int base);		（C++11 起）

std::uintmax_t strtoumax(const char* nptr, char** endptr, int base);		（C++11 起）

。解釋一個整數值，一個位元組串所指向的nptr.

Function discards any whitespace characters until first non-whitespace character is found. Then it takes as many characters as possible to form a valid base-n (where n=base) integer number representation and converts them to an integer value. The valid integer value consists of the following parts:

（可選的） plus or minus sign
（可選的） prefix (0) indicating octal base (applies only when the base is 8)
（可選的） prefix (0x or 0X) indicating hexadecimal base (applies only when the base is 16)
a sequence of digits

The set of valid digits for base-2 integer is 01, for base-3 integer is 012, and so on. For bases larger than 10, valid digits include alphabetic characters, starting from Aa for base-11 integer, to Zz for base-36 integer. The case of the characters is ignored.

。的功能設置的指針所指向的endptr指向過去的字元的最後一個字元解釋。 endptr是NULL，被忽視。

。如果nptr是空的，或者沒有預期的形式，無需轉換，（如果enptr是不NULL的nptr）的值存儲在指向的對象的endptr.

[编辑] 。參數。

nptr	-	。 null結尾的位元組串的指針進行解釋。 Original: pointer to the null-terminated byte string to be interpreted The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
endptr	-	。字元指針的指針. Original: pointer to a pointer to character. The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
base	-	。「基地」的解釋的整數值。 Original: base of the interpreted integer value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

===。返回值。===

。如果成功的話，一個整數值對應的內容str退貨。.
Original:
If successful, an integer value corresponding to the contents of str is returned.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
。如果轉換的值落在相應的返回類型的範圍，發生範圍錯誤（設置errno到ERANGE）和INTMAX_MAX，INTMAX_MIN，UINTMAX_MAX或0返回，適當.
Original:
If the converted value falls out of range of corresponding return type, a range error occurs (setting errno to ERANGE) and INTMAX_MAX, INTMAX_MIN, UINTMAX_MAX or 0 is returned, as appropriate.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
。如果沒有可以進行轉換，0返回.
Original:
If no conversion can be performed, 0 is returned.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

[编辑] 。為例。

#include <iostream>
#include <string>
#include <cinttypes>
 
int main()
{
    std::string str = "helloworld";
    std::intmax_t val = std::strtoimax(str.c_str(), nullptr, 36);
    std::cout << str << " in base 36 is " << val << " in base 10\n";
 
    char* nptr;
    val = std::strtoimax(str.c_str(), &nptr, 30);
    if(nptr != &str[0] + str.size())
        std::cout << str << " in base 30 is invalid."
                  << " The first invalid digit is " << *nptr << '\n';
}

Output:

helloworld in base 36 is 1767707668033969 in base 10
helloworld in base 30 is invalid. The first invalid digit is w

[编辑] 。另請參閱。


wcstoimax wcstoumax （C++11）（C++11）	寬字元串轉換std::intmax_t或std::uintmax_t Original: converts a wide string to std::intmax_t or std::uintmax_t The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函數） [edit]

strtol strtoll	一個位元組的字元串轉換為整數的值 Original: converts a byte string to an integer value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函數） [edit]

strtoul strtoull	一個無符號整數的值轉換為位元組字元串 Original: converts a byte string to an unsigned integer value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函數） [edit]

C documentation for strtoimax, strtoumax

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std::strtoimax, std::strtoumax

[编辑] 。參數。

[编辑] 。為例。

[编辑] 。另請參閱。

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