javascript "select all that start with"
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I am making a PDF order form for my small window installation business. The form has a table with different characteristics of the windows. Unfortunately, the three window manufacturers have different names for the same physical options. I came up with a solution of putting (3) fields on top of each other in the same table slot, and I named them all starting with the brand name they are pertinent to. Now I am trying to create a dropdown field that has a selector of the brands and controls which fields will show up when I select that brand name. I am trying to set a custom calculation scrip which depending on the brand name selects all fields starting with the same word and displays them. That way I can display only the pertinent field out of the three that are on top of each other. I have the following code:

    this.getField("Amerimax").display = event.value == "Amerimax" ? display.visible : display.hidden;
    this.getField("Anlin").display = event.value == "Anlin" ? display.visible : display.hidden;
    this.getField("MonteVerde").display = event.value == "MonteVerde" ? display.visible : display.hidden;

but it doesn't seem to work. Can someone suggest a "select all fields that start with (a certain word) and display it" code?