5 re convert binary to string
In MySQL, transcoding names are the same as the corresponding character set names. For example, this statement converts the string 'abc' in the default character set to the corresponding string in the utf8 character set:. The type for the result can be one of the following values:. As of MySQL 5. Normally, you cannot compare a BLOB value or other binary string in case-insensitive fashion because binary strings have no character set, and thus no concept of lettercase.
Comparisons of the result use the string collation. For example, if the character set of the result has a case-insensitive collation, a LIKE operation is not case sensitive:. To use a different character set, substitute its name for latin1 in the preceding statement. To perform lettercase conversion, convert the string to a nonbinary string:. The functions also can be useful for sorting ENUM columns in lexical order. Normally, sorting of ENUM columns occurs using the internal numeric values.
The bin , oct , dec , hex functions turn a integer into binary, octal, decimal or hex strings. The Int function turns a character into an integer, and the Char function turns an integer into a character. If you're deeply attached to C-style printf functionality, you'll be able to use a Julia macro which are called by prefacing them with the sign:. To read from a string into an array, you can use the IOBuffer function.
This is available with a number of Julia functions including printf. Here's a string of data it could have been read from a file:. Now you can "read" this string using functions such as readdlm , the "read with delimiters" function:. Sometimes you want to do things to strings that you can do better with arrays.
You can explode the pathname string into an array of character objects, using collect , which gathers the items in a collection or string into an array:. If you want to know whether a string contains a specific character, use the general-purpose in function. The contains function, which accepts two strings, is more generally useful, because you can use substrings with one or more characters. Notice that you place the container first, then the string you're looking for:. You can get the location of the first occurrence of a substring using search.
The second argument can be a single character, a vector or a set of characters, a string, or a regular expression:. This search is for the first occurrence of any of the set of characters, and 'o' was in the second position. For some tasks, you might prefer to use searchindex , which returns either the start index or The replace function returns a new string with a substring of characters replaced with something else:. Usually the third argument is another string, as here.
But you can also supply a function that processes the result:. That's because you can't change a string — they're immutable. You can use regular expressions to find matches for substrings.
Some functions that accept a regular expression are:. A letter preceded by a space is repeated three times:. Here I've loaded the complete text of "The Adventures of Sherlock Holmes" from a file into the string called text:. To use the possibility of a match as a Boolean condition, suitable for use in an if statement for example, use ismatch. The word "opium" does appear in the text, but only in lower-case, hence the first false result — regular expressions are case-sensitive.
The second search, a case-insensitive search set by the flag? There's an alternative syntax for adding regex modifiers, such as case-insensitive matches. Notice the "i" following the regex string:. With the eachmatch function, you apply the regex to the string to produce an iterator. For example, to look for substrings in our text matching the letters "L", followed by some other characters, ending with "ed":.
The result in lmatch is an iterable object containing all the matches, as RegexMatch objects. Now we can work through the iterator and look at each match in turn.
You can access a number of fields of the RegexMatch, to extract information about the match. Now the lmatches array contains the matching substrings, which you can inspect any way you want:. The basic match function looks for the first match for your regex. To write to a string, you can use a Julia stream. The sprint String Print function lets you use a function as the first argument, and uses the function and the rest of the arguments to send information to a stream.
For example, consider the following function, f. The body of the function maps an anonymous 'print' function over the arguments, enclosing them with angle brackets.
When used by sprint , the function f processes the remaining arguments and sends them to the stream, which, with sprint , is a string. Functions like println can take an IOBuffer or stream as their first argument. This lets you print to streams instead of printing to the standard output device:. After this, the in-memory stream called iobuffer is full of numbers and newlines, even though nothing was printed on the terminal. To copy the contents of iobuffer from the stream to a string or array, you can use take!