Hi,How to align text?

Hi,

   var label1= new sap.m.Label();

   label1.setText("Material Purchase Requisition");

   label1.setTextAlign(new sap.ui.core.TextAlign.Center);

above one is my code

and below is my error

Uncaught TypeError: string is not a function

what might be my mistake and please let me know is there any chance of adding CSS directly in  .js file?

Thanks in advance

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