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totalbalancetemp = (Number(this.balance)) + (Number(this.pastAmount));

My totalbalancetemp is returning undefined whereas this.balance is equal to 34 and this.pastAmount is equal to 23.

I have this in controller and displaying totalbalancetemp using exp in html

totalbalancetemp = (Number(this.balance)) + (Number(this.pastAmount));

My totalbalancetemp is returning undefined whereas this.balance is equal to 34 and this.pastAmount is equal to 23.

I have this in controller and displaying totalbalancetemp using exp in html

• javascript
• typescript
• casting

Share Improve this question Follow edited Mar 8, 2017 at 11:57 Simon West 3,78811 gold badge2828 silver badges2828 bronze badges asked Mar 8, 2017 at 8:25 johnjohn 2111 gold badge11 silver badge22 bronze badges 1

• if totalbalancetemp is a property of the ponent. then shouldn't you call it by this.totalbalancetemp – Thirueswaran Rajagopalan Commented Mar 8, 2017 at 8:28

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5 Answers 5

Sorted by: Reset to default 2

Supply the proper type.

let totalbalancetemp:number = balance + pastAmount

This will throw an error, because you are now guaranteeing that totalbalancetemp will be a number.

The type String is not assignable to type 'number'

Try the following:

let balance:string = '34',
    pastAmount:string = '23',
    totalbalancetemp:number = 0

totalbalancetemp = Number(balance) + Number(pastAmount)

alert(totalbalancetemp)

totalbalancetemp = (Number(this.balance)) + (Number(this.pastAmount));

please try this it should work

totalbalancetemp:number = (+this.balance) + (+this.pastAmount);

var totalbalancetemp = null; this.balance = 34; this.pastAmount = 23; 

totalbalancetemp = (Number(this.balance)) + (Number(this.pastAmount));

alert(totalbalancetemp);

-->totalbalancetemp - Define Variable (or) any type

totalbalancetemp should be replaced by this.totalbalancetemp if it's part of the angular 2 ponent

Do a +this.balance in the .ts file or this.balance*1 or this.balance/1 on in the template file.

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