如何验证空白/空白? [角度2] [英] How to validate white spaces/empty spaces? [Angular 2]

问题描述

我想避免我的angular 2格式出现空白/空白? 是否有可能? 该怎么办?

I would like to avoid white spaces/empty spaces in my angular 2 form? Is it possible? How can this be done?

推荐答案

也许本文可以为您在这种方法中，您必须使用FormControl，然后监视值的更改，然后将掩码应用于该值.一个例子应该是:

In this approach, you have to use FormControl then watch for value changes and then apply your mask to the value. An example should be:

...
form: FormGroup;
...


ngOnInit(){
    this.form.valueChanges
            .map((value) => {
                // Here you can manipulate your value
                value.firstName = value.firstName.trim();
                return value;
            })
            .filter((value) => this.form.valid)
            .subscribe((value) => {
               console.log("Model Driven Form valid value: vm = ",JSON.stringify(value));
            });

}

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