Accessing and Storing Functions: Difference between revisions

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<p style="margin-left:20pt;">Returns the formatted value of field <i>name</i> <span style="font-family: monospace,monospace; font-size:1em;">album</span>.
<p style="margin-left:20pt;">Returns the formatted value of field <i>name</i> <span style="font-family: monospace,monospace; font-size:1em;">album</span>.
Note that this is equivalent to <span style="font-family: monospace,monospace; font-size:1em;">[album]</span>.</p>
Note that this is equivalent to <span style="font-family: monospace,monospace; font-size:1em;">[album]</span>.</p>
| {{Function Example Item|field(date, 0)}}
{{Function Example Item|field(date, 0)}}
<p style="margin-left:20pt;">Returns the raw, unformatted value stored in the <span style="font-family: monospace,monospace; font-size:1em;">date</span> field.
<p style="margin-left:20pt;">Returns the raw, unformatted value stored in the <span style="font-family: monospace,monospace; font-size:1em;">date</span> field.
Note that this is equivalent to <span style="font-family: monospace,monospace; font-size:1em;">[date,0]</span>.</p>
Note that this is equivalent to <span style="font-family: monospace,monospace; font-size:1em;">[date,0]</span>.</p>

Revision as of 21:05, 23 January 2016

The functions in this section access field values, store and load global variables, access file tags, and access note fields.

Field(…)

Returns a field's value.
Description [[{{{name}}}()|{{{name}}}]]({{{arguments}}})

{{{description}}}

Examples {{{examples}}}
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The Field() function returns the value stored in field name. The format of return is selected by mode.

Available mode values:

0Raw, unformatted data
1Formatted data

Argument mode is optional (defaults to 1).

Template:Function Example Box Template:Function Example Item

Returns the formatted value of field name album. Note that this is equivalent to [album].

Template:Function Example Item

Returns the raw, unformatted value stored in the date field. Note that this is equivalent to [date,0].

|}

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Load(…)

Outputs the value of a global variable.
Description load(varname)

Loads and outputs the value of the specified global variable varname that has been previously stored with Save().

Examples load(var1)

Loads and outputs the previous stored value of the global variable named var1. If var1 has not been previously stored, the output will be empty.

save(math(1 + 2), sum)load(sum)

Saves the output of the Math() function into sum, and then loads and outputs the value of sum, which is 3.

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Note(…)

Retrieve note fields.
Description note(field label, field type, occurrence)

The Note() function retrieves information from a Media Center Note. Specifically, it returns the contents associated with a field label, of a given field type. The Nth occurrence may be requested. Notes data may be simple text, or associated with defined a field label. Currently the only type of field label is contact information. The first line of a Note is associated with the omnipresent field label Name.

The field type selects the specific sub-type for a given field label, and occurrence selects which instance of several field label / field type pairs is returned. The occurrence value is zero-based.

Argument field type is optional (defaults to FIRST AVAILABLE).

Argument occurrence is optional (defaults to 0).

Examples note(phone)

Returns the value found in the first Phone field label. If no Phone label exists, nothing is returned.

note(phone, home)

Returns the value found in the first Home field type from the Phone field label. If the Phone label, Home type does not exists, nothing is returned.

note(phone, home, 1)

Same as the previous example, but the second instance of the field type is selected instead of the first, since occurrence is zero-based.

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Save(…)

Saves a value to a global variable.
Description save(value, variable, mode)

This Save() function saves the value into the specified global variable, and optionally will return that value if mode is set. Once a global variable has been created using Save(), that variable's value is available for use with either Load() or the pseudo-field "[variable]".

0Suppress output
1Output variables value

Argument mode is optional (defaults to 0).

Examples save(Much Money, local_bank)

Saves the value Much Money into the global variable local_bank.

save(More Money, My Bank, 1)

Saves More Money into My Bank and outputs the variables value More Money.

save(math([duration,0] / 60), durmins)if(compare([durmins], >, 5.0), Long Track, Short Track)

Saves the calculated duration in minutes into the variable durmins. Notice that subsequent expressions fragments such as the if(compare()...) may now use the pseudo-field [durmins] as shorthand for load(durmins).

Additional Examples

Generating statistics
Generating album track count
Generating album ratings
Highlighting playing album
Expand a sublist into a superset
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SaveAdd(…)

Adds to a global variable.
Description saveadd(variable, value, mode)

The SaveAdd() function adds value to a global variable either numerically or as a list item. The mode argument indicates how variable is modified.

Available mode values:

0Add numeric value (integer or decimal) to variable
1Append string value as a list item to variable
2Prepend string value as a list item to variable

Argument mode is optional (defaults to 0).

Examples saveadd(v, 1)

Numerically increments the global variable v by 1.

saveadd(v, math(2 - 6))

Numerically increments the global variable v by the outcome of the Math(), which is -4.

load(foo, v)saveadd(v, bar, 1)load(v)

Loads value foo into variable v, then appends the value bar as a list item, and the final load(v) expression outputs the result of foo; bar.

load(That, v)saveadd(v, This, 2)load(v)

Similar to the previous example, but using the prepend mode, resulting in the output This; That.

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Tag(…)

Returns a file's physical tag.
Description tag(tag name)

The Tag() function reads and returns the value of tag name directly from a file. The Media Center Library database is not used with Tag(), and instead the specified file is read for the requested tag. The spelling and letter case of the tag name must match exactly those stored in the file. Performance note: This function must open and read the actual file, so its performance is significantly slower than other functions which operate on database fields.

Examples tag(My Personal Tag)

This will return the value from the tag named My Personal Tag from file referenced by the [filename] field.

tag(Gapless Header)

Returns the Gapless Header tag value, often contained in an mp3 file.

tag(exif: Date)

Returns the raw date data from the EXIF data saved inside a jpg file.

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