1. 在td上添加属性：formula，无需设定具体值
    1. <table>
    2.     <tr>
    3.         <td>1</td>
    4.     </tr>
    5.     <tr>
    6.         <td>19</td>
    7.     </tr>
    8.     <tr>
    9.         <td formula>SUM(A1:A2)</td>
    10.     </tr>
    11. </table>
    1. td中书写具体的公式即可，如：SUM(A1:A2)，需要特别注意的是，公式无需加上=号，如=SUM(A1:A2)

    支持公式如下：

    1. private static Function[] produceFunctions() {
    2.         Function[] retval = new Function[368];
    4.         retval[0] = new Count();
    5.         retval[FunctionID.IF] = new IfFunc(); //nominally 1
    6.         retval[2] = LogicalFunction.ISNA;
    7.         retval[3] = LogicalFunction.ISERROR;
    8.         retval[FunctionID.SUM] = AggregateFunction.SUM; //nominally 4
    9.         retval[5] = AggregateFunction.AVERAGE;
    10.         retval[6] = AggregateFunction.MIN;
    11.         retval[7] = AggregateFunction.MAX;
    12.         retval[8] = new RowFunc(); // ROW
    13.         retval[9] = new Column();
    14.         retval[10] = new Na();
    15.         retval[11] = new Npv();
    16.         retval[12] = AggregateFunction.STDEV;
    17.         retval[13] = NumericFunction.DOLLAR;
    18.         retval[14] = new Fixed();
    19.         retval[15] = NumericFunction.SIN;
    20.         retval[16] = NumericFunction.COS;
    21.         retval[17] = NumericFunction.TAN;
    22.         retval[18] = NumericFunction.ATAN;
    23.         retval[19] = NumericFunction.PI;
    24.         retval[20] = NumericFunction.SQRT;
    25.         retval[21] = NumericFunction.EXP;
    26.         retval[22] = NumericFunction.LN;
    27.         retval[23] = NumericFunction.LOG10;
    28.         retval[24] = NumericFunction.ABS;
    29.         retval[25] = NumericFunction.INT;
    30.         retval[26] = NumericFunction.SIGN;
    31.         retval[27] = NumericFunction.ROUND;
    32.         retval[28] = new Lookup();
    33.         retval[29] = new Index();
    34.         retval[30] = new Rept();
    35.         retval[31] = TextFunction.MID;
    36.         retval[32] = TextFunction.LEN;
    37.         retval[33] = new Value();
    38.         retval[34] = BooleanFunction.TRUE;
    39.         retval[35] = BooleanFunction.FALSE;
    40.         retval[36] = BooleanFunction.AND;
    41.         retval[37] = BooleanFunction.OR;
    42.         retval[38] = BooleanFunction.NOT;
    43.         retval[39] = NumericFunction.MOD;
    44.         // 40: DCOUNT
    45.         retval[41] = new DStarRunner(DStarRunner.DStarAlgorithmEnum.DSUM);
    46.         // 42: DAVERAGE
    47.         retval[43] = new DStarRunner(DStarRunner.DStarAlgorithmEnum.DMIN);
    48.         retval[44] = new DStarRunner(DStarRunner.DStarAlgorithmEnum.DMAX);
    49.         // 45: DSTDEV
    50.         retval[46] = AggregateFunction.VAR;
    51.         // 47: DVAR
    52.         retval[48] = TextFunction.TEXT;
    53.         // 49: LINEST
    54.         retval[50] = new Trend();
    55.         // 51: LOGEST
    56.         // 52: GROWTH
    58.         retval[56] = FinanceFunction.PV;
    59.         retval[57] = FinanceFunction.FV;
    60.         retval[58] = FinanceFunction.NPER;
    61.         retval[59] = FinanceFunction.PMT;
    62.         retval[60] = new Rate();
    63.         retval[61] = new Mirr();
    64.         retval[62] = new Irr();
    65.         retval[63] = NumericFunction.RAND;
    66.         retval[64] = new Match();
    67.         retval[65] = DateFunc.instance;
    68.         retval[66] = new TimeFunc();
    69.         retval[67] = CalendarFieldFunction.DAY;
    70.         retval[68] = CalendarFieldFunction.MONTH;
    71.         retval[69] = CalendarFieldFunction.YEAR;
    72.         retval[70] = WeekdayFunc.instance;
    73.         retval[71] = CalendarFieldFunction.HOUR;
    74.         retval[72] = CalendarFieldFunction.MINUTE;
    75.         retval[73] = CalendarFieldFunction.SECOND;
    76.         retval[74] = new Now();
    77.         retval[75] = new Areas();
    78.         retval[76] = new Rows();
    79.         retval[77] = new Columns();
    80.         retval[FunctionID.OFFSET] = new Offset(); //nominally 78
    82.         retval[82] = TextFunction.SEARCH;
    83.         retval[83] = MatrixFunction.TRANSPOSE;
    85.         // 86: TYPE
    87.         retval[97] = NumericFunction.ATAN2;
    88.         retval[98] = NumericFunction.ASIN;
    89.         retval[99] = NumericFunction.ACOS;
    90.         retval[FunctionID.CHOOSE] = new Choose(); //nominally 100
    91.         retval[101] = new Hlookup();
    92.         retval[102] = new Vlookup();
    94.         retval[105] = LogicalFunction.ISREF;
    96.         retval[109] = NumericFunction.LOG;
    98.         retval[111] = TextFunction.CHAR;
    99.         retval[112] = TextFunction.LOWER;
    100.         retval[113] = TextFunction.UPPER;
    101.         retval[114] = TextFunction.PROPER;
    102.         retval[115] = TextFunction.LEFT;
    103.         retval[116] = TextFunction.RIGHT;
    104.         retval[117] = TextFunction.EXACT;
    105.         retval[118] = TextFunction.TRIM;
    106.         retval[119] = new Replace();
    107.         retval[120] = new Substitute();
    108.         retval[121] = new Code();
    110.         retval[124] = TextFunction.FIND;
    111.         // 125: CELL
    113.         retval[126] = LogicalFunction.ISERR;
    114.         retval[127] = LogicalFunction.ISTEXT;
    115.         retval[128] = LogicalFunction.ISNUMBER;
    116.         retval[129] = LogicalFunction.ISBLANK;
    117.         retval[130] = new T();
    118.         // 131: N
    119.         // 140: DATEVALUE
    120.         // 141: TIMEVALUE
    121.         // 142: SLN
    122.         // 143: SYD
    123.         // 144: DDB
    125.         retval[FunctionID.INDIRECT] = null; // Indirect.evaluate has different signature
    127.         retval[162] = TextFunction.CLEAN;
    129.         retval[163] = MatrixFunction.MDETERM;
    130.         retval[164] = MatrixFunction.MINVERSE;
    131.         retval[165] = MatrixFunction.MMULT;
    133.         retval[167] = new IPMT();
    134.         retval[168] = new PPMT();
    135.         retval[169] = new Counta();
    137.         retval[183] = AggregateFunction.PRODUCT;
    138.         retval[184] = NumericFunction.FACT;
    140.         // 189: DPRODUCT
    141.         retval[190] = LogicalFunction.ISNONTEXT;
    143.         retval[194] = AggregateFunction.VARP;
    144.         // 195: DSTDEVP
    145.         // 196: DVARP
    146.         retval[197] = NumericFunction.TRUNC;
    147.         retval[198] = LogicalFunction.ISLOGICAL;
    148.         // 199: DCOUNTA
    150.         //204: USDOLLAR (YEN in BIFF3)
    151.         //205: FINDB
    152.         //206: SEARCHB
    153.         //207: REPLACEB
    154.         //208: LEFTB
    155.         //209: RIGHTB
    156.         //210: MIDB
    157.         //211: LENB
    158.         retval[212] = NumericFunction.ROUNDUP;
    159.         retval[213] = NumericFunction.ROUNDDOWN;
    160.         //214: ASC
    161.         //215: DBCS (JIS in BIFF3)
    162.         retval[216] = new Rank();
    163.         retval[219] = new Address();
    164.         retval[220] = new Days360();
    165.         retval[221] = new Today();
    166.         //222: VBD
    168.         retval[227] = AggregateFunction.MEDIAN;
    169.         retval[228] = new Sumproduct();
    170.         retval[229] = NumericFunction.SINH;
    171.         retval[230] = NumericFunction.COSH;
    172.         retval[231] = NumericFunction.TANH;
    173.         retval[232] = NumericFunction.ASINH;
    174.         retval[233] = NumericFunction.ACOSH;
    175.         retval[234] = NumericFunction.ATANH;
    176.         retval[235] = new DStarRunner(DStarRunner.DStarAlgorithmEnum.DGET);
    178.         // 244: INFO
    180.         // 247: DB
    181.         // 252: FEQUENCY
    182.         retval[252] = Frequency.instance;
    184.         retval[FunctionID.EXTERNAL_FUNC] = null; // ExternalFunction is a FreeRefFunction, nominally 255
    186.         retval[261] = new Errortype();
    188.         retval[269] = AggregateFunction.AVEDEV;
    189.         // 270: BETADIST
    190.         // 271: GAMMALN
    191.         // 272: BETAINV
    192.         // 273: BINOMDIST
    193.         // 274: CHIDIST
    194.         // 275: CHIINV
    195.         retval[276] = NumericFunction.COMBIN;
    196.         // 277: CONFIDENCE
    197.         // 278:CRITBINOM
    198.         retval[279] = new Even();
    199.         // 280: EXPONDIST
    200.         // 281: FDIST
    201.         // 282: FINV
    202.         // 283: FISHER
    203.         // 284: FISHERINV
    204.         retval[285] = NumericFunction.FLOOR;
    205.         // 286: GAMMADIST
    206.         // 287: GAMMAINV
    207.         retval[288] = NumericFunction.CEILING;
    208.         // 289: HYPGEOMDIST
    209.         // 290: LOGNORMDIST
    210.         // 291: LOGINV
    211.         // 292: NEGBINOMDIST
    212.         // 293: NORMDIST
    213.         // 294: NORMSDIST
    214.         // 295: NORMINV
    215.         // 296: NORMSINV
    216.         // 297: STANDARDIZE
    217.         retval[298] = new Odd();
    218.         // 299: PERMUT
    219.         retval[300] = NumericFunction.POISSON;
    220.         // 301: TDIST
    221.         // 302: WEIBULL
    222.         retval[303] = new Sumxmy2();
    223.         retval[304] = new Sumx2my2();
    224.         retval[305] = new Sumx2py2();
    225.         // 306: CHITEST
    226.         // 307: CORREL
    227.         // 308: COVAR
    228.         // 309: FORECAST
    229.         // 310: FTEST
    230.         retval[311] = new Intercept();
    231.         // 312: PEARSON
    232.         // 313: RSQ
    233.         // 314: STEYX
    234.         retval[315] = new Slope();
    235.         // 316: TTEST
    236.         // 317: PROB
    237.         retval[318] = AggregateFunction.DEVSQ;
    238.         retval[319] = AggregateFunction.GEOMEAN;
    239.         // 320: HARMEAN
    240.         retval[321] = AggregateFunction.SUMSQ;
    241.         // 322: KURT
    242.         // 323: SKEW
    243.         // 324: ZTEST
    244.         retval[325] = AggregateFunction.LARGE;
    245.         retval[326] = AggregateFunction.SMALL;
    246.         // 327: QUARTILE
    247.         retval[328] = AggregateFunction.PERCENTILE;
    248.         // 329: PERCENTRANK
    249.         retval[330] = new Mode();
    250.         // 331: TRIMMEAN
    251.         // 332: TINV
    253.         retval[336] = TextFunction.CONCATENATE;
    254.         retval[337] = NumericFunction.POWER;
    256.         retval[342] = NumericFunction.RADIANS;
    257.         retval[343] = NumericFunction.DEGREES;
    258.         retval[344] = new Subtotal();
    259.         retval[345] = new Sumif();
    260.         retval[346] = new Countif();
    261.         retval[347] = new Countblank();
    263.         // 350: ISPMT
    264.         // 351: DATEDIF
    265.         // 352: DATESTRING
    266.         // 353: NUMBERSTRING
    267.         retval[354] = new Roman();
    269.         // 358: GETPIVOTDATA
    270.         retval[359] = new Hyperlink();
    271.         // 360: PHONETIC
    272.         // 361: AVERAGEA
    273.         retval[362] = MinaMaxa.MAXA;
    274.         retval[363] = MinaMaxa.MINA;
    275.         // 364: STDEVPA
    276.         // 365: VARPA
    277.         // 366: STDEVA
    278.         // 367: VARA
    279.     }