MTA:Eir/FileSystem/file/readBoolean

From Multi Theft Auto: Wiki

This function attempts to read a boolean (native type) from a file and return it. The amount of bytes read should be one.

Syntax

boolean file.readBoolean ()

Returns

Returns a boolean if it was successfully read from the file, nil otherwise.

Example

Click to collapse [-]
Client

This snippet demonstrates a variable file format that stores player properties depending on whether they are required. 

local function saveLocalPlayerState( theFile, saveDetails )
    local player = localPlayer;

    -- Write basic details about the player instance.
    theFile.writeShort( getElementModel( player ) );
    theFile.writeInt( getPlayerMoney() );
    
    -- Next write down special details given by the game.
    local isQuickSave = saveDetails.isQuickSave and true or false;

    theFile.writeBoolean( isQuickSave );

    if not ( isQuickSave ) then
        -- Save things like player position, dimension and interior.
        local posX, posY, posZ = getElementPosition( player );
        local dimension, interior = getElementDimension( player ), getElementInterior( player );

        theFile.writeDouble( posX ); theFile.writeDouble( posY ); theFile.writeDouble( posZ );
        theFile.writeShort( dimension ); theFile.writeShort( interior );
    end

    -- Save the time this snapshot was taken.
    local realTime = getRealTime();

    theFile.writeShort( realTime.minute ); theFile.writeShort( realTime.hour );
    theFile.writeShort( realTime.monthday ); theFile.writeShort( realTime.month + 1 ); theFile.writeShort( realTime.year + 1900 );
    return true;
end

local function readBasicData( operator, callback )
    local data = operator();

    if ( data ) then
        callback( data );
    end
end

-- Function to restore details from a snapshot file stream.
local function loadLocalPlayerState( theFile )
    local player = localPlayer;
    local saveDetails = {};

    -- Restore the basic information.
    readBasicData( theFile.readShort, function(model) setElementModel( player, model ); end );
    readBasicData( theFile.readInt, function(money) setPlayerMoney(money); end );

    -- Read advanced parameters,
    local isQuickSave = theFile.readBoolean();
    saveDetails.isQuickSave = isQuickSave;

    if not ( isQuickSave ) then
        -- Restore advanced details.
        local posX, posY, posZ = theFile.readDouble(), theFile.readDouble(), theFile.readDouble();
        local dimension, interior = theFile.readShort(), theFile.readShort();

        -- Set them, if read correctly.
        if ( interior ) then
            setElementPosition( player, posX, posY, posZ );
            setElementDimension( player, dimension );
            setElementInterior( player, interior );
        end
    end

    -- Get the time the snapshot was taken at.
    saveDetails.saveTime = {
        minute = theFile.readShort(),
        hour = theFile.readShort(),
        monthday = theFile.readShort(),
        month = theFile.readShort(),
        year = theFile.readShort()
    };

    -- Return the save details so the runtime can react accordingly.
    return saveDetails;
end

-- Command to save a complete snapshot of the player.
addCommandHandler( "save",
    function()
        local saveDetails =
        {
            isQuickSave = false
        };

        local saveFile = fileCreate( "savestate.dat" );

        if ( saveFile ) then
            saveLocalPlayerState( saveFile, saveDetails );

            saveFile.destroy();

            outputChatBox( "successfully saved complete player status" );
        end
    end
);

-- Command to save a quick savestate.
addCommandHandler( "qsave",
    function()
        local saveDetails =
        {
            isQuickSave = true
        };

        local saveFile = fileCreate( "savestate.dat" );

        if ( saveFile ) then
            saveLocalPlayerState( saveFile, saveDetails );

            saveFile.destroy();

            outputChatBox( "successfully saved quick player status" );
        end
    end
);

-- Command to load a savestate from disk.
addCommandHandler( "loadstate",
    function()
        if not ( fileExists( "savestate.dat" ) ) then
            return;
        end

        local saveFile = fileOpen( "savestate.dat" );

        if ( saveFile ) then
            local saveData = loadLocalPlayerState( saveFile );

            saveFile.destroy();

            outputChatBox( "restored from a save (date was " .. saveData.saveTime.monthday .. "." .. saveData.saveTime.month .. "." .. saveData.saveTime.year .. ")" );
        end
    end
);

FileSystem File Functions

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