带参数的Javascript回调函数

Question

The call:

Query.GetDepartments(AcademicYears, function (result) {
                    console.log(result)
                })

The function:

exports.GetDepartments = function (callback, AcademicYears) {
    CountAcademicYears = Object.keys(AcademicYears).length;
    switch (CountAcademicYears) {
        case 1:
            AcademicYear1 = AcademicYears[0].Year;
            AcademicYear1 = String(AcademicYear1);
            query = "SELECT [p_departement], [depcode], [departement], [schooljaar] FROM [SA_Departement] WHERE schooljaar='" + AcademicYear1 + "'";
            console.log(query);
            (async function () {
                try {
                    let result = await globalConnectionInfordat.request()
                        .query(query);
                    callback(result.recordset);
                } catch (err) {
                    console.log(err);
                }
            })();
            break;
        ..........

    }
}

This gives me this error:

'Incorrect syntax near the keyword \'function\'.',

For some reason, the string isn't read out alright(I think)? Any ideas?

I just need to know how to pass an argument to the function?

EDIT

I had to move the words around for some reason: function (Academicyears, callback) is working.

Thanks for the help!

Answer 1

callback is a local variable. It only exists inside function (query, callback) { /* ... */ } .

You can't use it from outside that function (ie in the anonymous function you pass to ExecuteSql ).

You would need to create another reference to that function and then use that name:

this.ExecuteSql("SELECT ...", function a_named_function (result) {
            a_named_function(result);
        });

… but recursively calling that function makes no sense.

Answer 2

As per definition of "ExecuteSql", it accepts 2 param. 1. string 2. function.

So when you are calling that module.

it should be:

  this.ExecuteSql("your string", function (result) {
                   console.log(result);
                });

Hope this help you.