How to change control's background color when validation fails when controls have multiple validation

Here is the java script :

function ContainsControl(controlArray,arrayItem) {
    var result = { boolValue: false, indexValue: -1 };
    for (var i = 0; i < controlArray.length; i++) {
        if (controlArray[i]["control"] == arrayItem.control) {
            result.boolValue = true;
            result.indexValue = i;
            break;
        }
    }
    return result;
}
 
function SetBGColor() {
    var inputControlValidationResult = new Array();
    for (var i = 0; i < Page_Validators.length; i++) {
        var inputControl = document.getElementById(Page_Validators[i].controltovalidate);
        var arrayItem = { control: inputControl, valid: Page_Validators[i].isvalid ? 1 : 0 };
        var result = ContainsControl(inputControlValidationResult, arrayItem);
        if (result.boolValue) {
            inputControlValidationResult[result.indexValue].valid &= arrayItem.valid;
        }
        else {
            inputControlValidationResult.push(arrayItem);
        }
      
    }
    for (var i2=0; i2 < inputControlValidationResult.length; i2++) {
        inputControlValidationResult[i2].control.style.backgroundColor = inputControlValidationResult[i2].valid ? "" : "red";
    }
}

In order to run this script after client side validation but before page
 submission, you have to register this using some of the server side 
page events, I use the Page_Load :

protected void Page_Load(object sender, EventArgs e)
        {
            Page.ClientScript.RegisterOnSubmitStatement(GetType(), "onsubmit", "SetBGColor();");
        }