ReadINI ( iniCode ; keyName )

gets a value from a block of text structured like an INI file

Average rating: 4.2 (33 votes) Log in to vote

Joe Rovang - Show more from this author

Sample input:

ReadINI ( "function=ReadINI¶author=Joe Rovang"; "author" )

Sample output:

Joe Rovang

Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

/*

An INI file (or, for the purposes of this function, a block of "INI code") contains a series of return-separated entries (called "keys") which each begin with a key name, followed by an equals sign and some value to assign to the key. The ReadINI function is able to read the INI code and return the value associated with a requested keyName parameter. If the INI code makes use of section headers, the keyName parameter can be used to search only a specific section for the desired key (see details below).

Required function:
This function makes use of the TrimSpacesAndTabs custom function, which trims leading/trailing spaces and tabs. If you prefer not to use the TrimSpacesAndTabs function (perhaps your INI code won't contain tabs), you may change this expression's occurrences of "TrimSpacesAndTabs" to the native "Trim" function (or your preferred trimming custom function; note that custom functions which trim returns as well are acceptable here).

Assigning key names:
• The key name is the part of the key to the left of the equals sign. Each key name should be unique (at least within its respective section).
• Any character is allowed in a key name except:
	° equals sign (marks the start of the key value)
	° return (marks the end of the key value)
	° semicolon (marks the start of a comment; see below)
	° hash character ("#") (has reserved meaning in keyName parameter)
• Square brackets may be used in key names, but avoid key names beginning with a left square bracket paired with a key value ending with a right square bracket (such a line would be interpreted as a section header instead; see below).

Assigning key values:
• The key value is the part of the key to the right of the equals sign. It can be any value (or empty).
• Any character is allowed in a key value except:
	° return (ends the key)
	° semicolon (marks the start of a comment; see below)

Assigning sections:
• A section header consists of an arbitrary section name surrounded by square brackets. Each section name should be unique.
• A section header must exist on its own line (no keys may be placed in the same line).
• Any character is allowed in a section name except:
	° return (marks the end of a section header line)
	° semicolon (marks the start of a comment; see below)
	° hash character ("#") (has reserved meaning in keyName parameter)
• All keys located under a section header are regarded as belonging to that section until a subsequent section header is encountered.
• Section nesting is not possible. You may, however, name your sections in such a way which gives a human reader the impression of a hierarchy (example: "[Section:Subsection]").
• If any keys are placed above your INI code's first section header, these keys are considered "global" (see "Getting results," below). If no section headers appear in your code, all keys are considered global.

Using comments:
• A semicolon denotes the start of a comment, which extends until a return character is encountered. Comments are ignored by the ReadINI function.
• A comment may be written on a standalone line, or it may be inline at the end of a section header or key value.

Using whitespace:
• Blank lines are ignored in the INI code, as are any lines not recognized as a section header or key.
• Leading and trailing spaces are ignored in the following locations:
	° outside the brackets of a section header
	° on either side of a section name (inside the brackets)
	° before a key name
	° on either side of a key's equals sign
	° at the end of a key value
	° before a comment (such as between a key value and an inline comment)
	° on either side of the keyName parameter (as well as on either side of the hash symbol therein)
• Leading/trailing tabs are also ignored in all above locations, as long as this function's expression continues to use a tab-trimming custom function instead of the native Trim function.

Getting results:
• If this function is given a keyName parameter matching a key name within the INI code, the function will return the value from the first key with a matching key name (regardless of section headers).
• If the keyName parameter includes a section name and a key name (separated with a hash character, "#"), the function will only search the specified section for the requested key name. (Example: "A#B" finds a key named "B" only among keys grouped under the section named "A".)
• If the keyName parameter begins with a hash character, the function will only search global keys (keys preceding any section header). (Example: "#B" finds a key named "B" only if it exists before any section headers.)
• If the requested key name has no match in the searched section/code (or if the requested key has an empty value), the function will return empty.
• Text formatting is returned intact if it was present in the original INI code and a non-empty key value is found.
• Searches performed using the keyName parameter are not case-sensitive.

*/

Let (
[
	code = Substitute ( iniCode; [ Char ( 10 ); ¶ ] ); // standardize returns
	countLines = ValueCount ( code );
	thisLineWithComment = GetValue ( code; 1 );
	otherLines = RightValues ( code; countLines - 1 );

	commentStart = Position ( thisLineWithComment; ";"; 1; 1 );
	thisLine = TrimSpacesAndTabs ( Replace (
		thisLineWithComment;
		commentStart;
		If ( commentStart > 0; Length ( thisLineWithComment ) );
		""
	) );
	thisLineLength = Length ( thisLine );

	findParam = keyName;
	findParamHashPos = Position ( findParam; "#"; 1; 1 );
	findGlobalOnly = ( findParamHashPos = 1 );
	findSection = TrimSpacesAndTabs ( Left ( findParam; findParamHashPos - 1 ) );
	findKey = TrimSpacesAndTabs ( Replace ( findParam; 1; findParamHashPos; "" ) );

	thisIsASectionHeader = ( Left ( thisLine; 1 ) = "[" ) and ( Right ( thisLine; 1 ) = "]" );
	thisIsTheSectionHeader =
		thisIsASectionHeader and
		( not IsEmpty ( findSection ) ) and
		( TrimSpacesAndTabs ( Middle ( thisLine; 2; thisLineLength - 2 ) ) = findSection );

	equalPos = Position ( thisLine; "="; 1; 1 );
	thisKeyName = TrimSpacesAndTabs ( If ( equalPos > 0; Left ( thisLine; equalPos - 1 ) ) );
	thisKeyValue = TrimSpacesAndTabs ( If ( equalPos > 0; Replace ( thisLine; 1; equalPos; "" ) ) )

];

Case (

/* What to do if the code has no lines */
countLines = 0;
	""; // end

/* What to do if the findKey is empty */
IsEmpty ( findKey );
	""; // end

/* What to do if you're looking for a section and you just found its header */
thisIsTheSectionHeader;
	ReadINI ( otherLines; "#" & findKey ); // remove header, rerun as global-key search

/* What to do if you're looking for a global key but you hit a section header */
findGlobalOnly and thisIsASectionHeader;
	""; // end

/* What to do if you're looking for a section but you haven't found it yet */
not IsEmpty ( findSection );
	ReadINI ( otherLines; findParam ); // try next line

/* What to do if you're looking for a key and you just found it */
( thisKeyName = findKey ) and ( not thisIsASectionHeader );
	thisKeyValue; // return its value

/* What to do failing all above */
	ReadINI ( otherLines; findParam ) // try next line

) // end Case

) // end Let

This function looks up a value from a block of text that's been structured like an INI file. This text can include section headers, such that your search can be limited to a section of your choosing. The text can also include INI-style comments (which will be ignored).

See comments in function expression for detailed usage notes. For more about INI files, see Wikipedia: http://en.wikipedia.org/wiki/INI_file

Comments

Note: these functions are not guaranteed or supported by BrianDunning.com. Please contact the individual developer with any questions or problems.

ReadINI ( iniCode ; keyName )

Comments

Support this website.

Support this website.