通过属性在对象数组中查找值的语法是什么？

Question

What is the syntax to find a value in an array object?

 var pStData = []; pStData.push({ st: 'WV', geom: 'xxx' }); pStData.push({ st: 'TX', geom: 'yyy' }); var sGeom = pStData.find(pStData => pStData.st == 'TX').geom; console.log(sGeom);

In my code, pStData.find(pStData => pStData.st == 'TX') is undefined .

Answer 1

Other than no jQuery there at all, you're defining the array as an array of objects. Define an object like this:

var pStData = {};
pStData['WV'] = {geom: 'xxx'};
pStData['TX'] = {geom: 'yyy'};

Then you can access simply by

var sGeom = pStData['WV'].geom;

You can also access it via

var sGeom = pStData.WV.geom;

Of course you don't need to define the object if you're only looking up a string value, for example this would work just as well.

var pStData = {};
pStData['WV'] = 'xxx';
pStData['TX'] = 'yyy';

However, defining it as an object does future proof your code, should you need to add extra data values later. Never be afraid to do a bit of future proofing, it can save a lot of work later.

Answer 2

Use this function:

 function findObjectInArrayByProperty(array, propertyName, propertyValue) {
      return array.find((o) => { return o[propertyName] === propertyValue });
 }

So, in your case:

 function findObjectInArrayByProperty(array, propertyName, propertyValue) { return array.find((o) => { return o[propertyName] === propertyValue }); } var pStData = []; pStData.push({ st: 'WV', geom: 'xxx' }); pStData.push({ st: 'TX', geom: 'yyy' }); var resultObj = findObjectInArrayByProperty(pStData, "st", "TX"); console.log(resultObj);

output -> { st: 'TX', geom: 'yyy' }