javascript - 传递调用结果时出现异常：TypeError：不是流星中的函数(Exception in delivering result of invoking : TypeError: is not a function in meteor)

Question

When I added in onSuccessCreateClass into meteor.call callback and this error come up.(当我将onSuccessCreateClass添加到meteor.call回调中时，出现此错误。)

dont know what is wrong here?(不知道这是怎么回事？) Exception in delivering result of invoking 'createClass': TypeError: this.onSuccessCreateClass is not a function at http://localhost:3000/app/client/components/MyClasses.jsx?044c7b228d4b33fcea4b9f3c05da6d82e5e6c8b7:37:11 at null._callback ( http://localhost:3000/packages/meteor.js?9730f4ff059088b3f7f14c0672d155218a1802d4:999:22 ) at _.extend._maybeInvokeCallback ( http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:3500:12 ) at .extend.dataVisible ( http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:3529:10 ) at http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:4365:7 at Array.forEach (native) at Function.(传递调用'createClass'的结果时发生异常：TypeError：this.onSuccessCreateClass不是http：// localhost：3000 / app / client / components / MyClasses.jsx？044c7b228d4b33fcea4b9f3c05da6d82e5e6c8b7：37：11处的函数。_callback（ http： //localhost:3000/packages/meteor.js?9730f4ff059088b3f7f14c0672d155218a1802d4:999:22 ）在_.extend._maybeInvokeCallback（ HTTP：//本地主机：3000 /包/ DDP-client.js 250b63e6c919c5383a0511ee4efbf42bb70a650f：3500：12 ）在.extend .dataVisible（ http：// localhost：3000 / packages / ddp-client.js？250b63e6c919c5383a0511ee4efbf42bb70a650f：3529：10 ）at http：// localhost：3000 / packages / ddp-client.js？250b63e6c919c5383a0511ee4efbf42bb707 at 600： Array Function的forEach（本机）。) .each._.forEach ( http://localhost:3000/packages/underscore.js?46eaedbdeb6e71c82af1b16f51c7da4127d6f285:149:11 ) at _.extend._runAfterUpdateCallbacks ( http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:4364:7 ) at _.extend._livedata_data ( http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:4354:10 ) at onMessage ( http://localhost:3000/packages/ddp-client.js?250b63e6c919c5383a0511ee4efbf42bb70a650f:3361:12 )(.each ._。forEach（ http：// localhost：3000 / packages / underscore.js？46eaedbdeb6e71c82af1b16f51c7da4127d6f285：149：11 ）位于_.extend._runAfterUpdateCallbacks（ http：// localhost：3000 / packages / ddp-client.js？ 250b63e6c919c5383a0511ee4efbf42bb70a650f：4364：7在_.extend._livedata_data）（ HTTP：//本地主机：3000 /包/ DDP-client.js 250b63e6c919c5383a0511ee4efbf42bb70a650f：4354：10 ）在的onMessage（ HTTP：//本地主机：3000 /包/ ddp- client.js？250b63e6c919c5383a0511ee4efbf42bb70a650f：3361：12 ）) onSuccessCreateClass() { console.log("Successfully created New Class") $("#createClassModal").modal('hide') $('#createClassModal').on('hidden.bs.modal', function () { $(this).find('form').trigger('reset') }) }, onPressSubmit(e) { e.preventDefault() const className = e.target.cname.value console.log(this.props.courseId) console.log(className) if (Meteor.user().classes.length !== 0) { console.log("Got Class") Meteor.call("createClass", this.props.courseId, className, function(error) { if (error) { console.log(error.reason) } else { this.onSuccessCreateClass() } }) } else { console.log("No Class") Meteor.call("createNewClass", this.props.courseId, className, function(error) { if (error) { console.log(error.reason) } else { this.onSuccessCreateClass() } }) } },   ask by phongyewtong translate from so

Answer 1

You should set this for callback in Meteor.call , because now this refers to the global scope or undefined if you are using strict mode .(您应该设置this在回调Meteor.call ，因为现在this指的是全球范围或undefined ，如果你使用的是strict mode 。)

In JavaScript, there is method .bind which allows set this for method(在JavaScript中，方法.bind允许为方法设置this值) Meteor.call("createClass", this.props.courseId, className, function(error) { if (error) { console.log(error.reason) } else { this.onSuccessCreateClass() } }.bind(this)) --(-) Meteor.call("createNewClass", this.props.courseId, className, function(error) { if (error) { console.log(error.reason) } else { this.onSuccessCreateClass() } }.bind(this))