Free jqGrid. Getting column names in conjunction with a cell - jqgrid

Question

I'm trying to implement a data fullness check with an error output that describes which cells were not filled in the line.
//get row id
var gr = $("#" + subgrid_table_id).jqGrid('getGridParam', 'selrow');
// check row select
if (gr != null) {
/*
var myGrid = $("#" + subgrid_table_id),
selRowId = myGrid.jqGrid('getGridParam', 'selrow'),
//get cell value:
col1Value = myGrid.jqGrid('getCell', selRowId, 'stage');
//get all colnames
var columnNames = myGrid.jqGrid('getGridParam','colNames');
//get column name by index:
var col1Name = columnNames[4];
if (col1Value == "") {
alert("This data is empty: "+col1Name);
}
else {
That is, everything seems to work, but when you change the number of columns, everything can go to waste. How can I link the column name to ColNames with its name in ColModel to get a dynamic solution?

Answer 1

First of all all parameters of jqGrid are saved in one object available by myGrid.jqGrid('getGridParam'). Thus var selRowId = myGrid.jqGrid('getGridParam', 'selrow'); is the same as p.selrow, where var p = myGrid.jqGrid('getGridParam');.
The columns will be identified by the index in the colModel: p.colModel[iCol]. On the other side the name property of the column will be known more frequently as the index of the column iCol. Moreover, there are exist the possibility to reorder the columns by drag and drop of the column headers. One need include sortable: true option of the grid to enable the possibility. The column order can be changed by columnChooser or by direct calls of the methods remapColumns or remapColumnsByName. Because of all the reasons it's recommend to save the name of columns (which will be never changed) instead of the column index.
To get the column index by the column name one can loop over colModel array and test the value of the name property. To speed-up such operation free jqGrid provided the map object iColByName as the option of jqGrid. Thus, if you know the column name cmName then you can use var iCol = p.iColByName[cmName]; to get the column index. The column in colModel will be p.colModel[iCol] and the text of the column header will be p.colNames[iCol].
By the way, I'm not sure that you correctly understand the value of colNames. The name of the parameter is not good, but it will be used because of the compatibility with the old version. The elements of the array colNames are HTML fragments, which will be placed in the column headers. One can have empty strings inside of colNames or to have the same headers for different columns. On the other side the name property of the colModel is the real name of the column. It can't be empty. One can't use duplicate names in different columns and the names can't contains spaces.
I hope that having the above information you will easy able to find full information about every column.
The final remark. There are three main methods, which can be used to get data of the grid: getCell, getRowData and getLocalRow. jqGrid get input data, formats the data and places the formatted HTML fragments in the cells (in <td>). Additionally jqGrid saves the original raw data in internal data parameter (which is array of items, represented the rows). The data parameter exists only in case of using local data (datatype: "local") or in case of loading the data from remote set (datatype: "json" or datatype: "xml"), but with loadonce: true option additionally. The methods getCell and getRowData unformats the data from the cell(s) (from <td>) and the method getLocalRow get you direct reference to internal JavaScript object from internal data, where the data of the row are already set. Thus, it's recommended to prefer to use getLocalRow instead of getCell or getRowData whenever the grid has local data.