Eve ng undefined error issues1/21/2023 In some cases we want to display array of elements only when array length greater than zero. To compare with other component string variables no need to use quotes. We should use quotes while comparing with staitc string inside an *ngIf. You will get “Parser Error: Bindings cannot contain assignments at column” error when you use an assignment operator inside *ngIf as shown below. It’s very common to misplace or forgot to use double equal or triple equal and people tend to use assignment operator (single equal) while compare strings for equality. Show electronics products related data To compare string for equality we can use double equal(=) or triple equal(=) operator inside *ngIf expression. To handle such scenarios, we can check if the object is undefined or null using *ngIf before displaying the data as shown below. The problem is for each property we display, we have to use safe navigation operator. We can use safe navigation operator ? to check for null or undefined. In traditional programming languages, will be writing if else conditions using flower brackets as shown below. The reason why I wrote two *ngIf blocks is I don’t know how *ngIf directive works in Angular. ngIf NullInjectorError: No provider for TemplateRef! error.*ngIf with async pipe and observable example.Compare Strings for equality using *ngIf.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |